Crystalline forms of nicotinamide furan riboside salts and nutritional supplements and pharmaceutical compositions comprising same

Abstract

The present invention relates to a process for the preparation of crystalline forms of nicotinamide furan riboside salts, in particular of pharmaceutically acceptable crystalline forms of nicotinamide furan riboside salts. The invention also relates to the crystalline form of the nicotinamide furanoriboside salt itself, in particular the hydrogen malate in crystalline form, and their use in nutritional supplements and pharmaceutical compositions.

Description

[0001] This application is a divisional application of an invention patent application with an international application date of July 20, 2020, a Chinese national application number of 202080066067.9, and an invention name of “Method for preparing nicotinamide furanoside salt, nicotinamide furanoside salt itself and its use”. Technical Field

[0002] The present invention relates to a method for preparing nicotinamide furanoside salts, in particular pharmaceutically acceptable nicotinamide furanoside salts. The present invention also relates to nicotinamide furanoside salts themselves, in particular carboxylate salts in crystalline form, and their use in nutritional supplements and pharmaceutical compositions. Background Art

[0003] Nicotinamide riboside (nicotinamide-β-D-ribofuranoside; CAS No. 1341-23-7)

[0004]

[0005] Nicotinamide adenine dinucleotide (NAD + / NADH and nicotinamide adenine dinucleotide phosphate (NADP + / NADPH). In addition, nicotinamide riboside is a niacin (vitamin B3) equivalent.

[0006] Nicotinamide riboside has been reported to increase NAD in liver and skeletal muscle in mice fed a high-fat diet. + In a transgenic mouse model of Alzheimer's disease, it also increased NAD levels in the cerebral cortex. + concentration and reduce the deterioration of cognitive function. For these reasons, nicotinamide riboside salts have been suggested for use in nutritional supplements and pharmaceutical compositions. In fact, the chloride salt of nicotinamide-β-D-ribofuranoside is a commercially available nutritional supplement.

[0007] However, the widespread use of these compounds as dietary supplements is limited by low yields, poor stereoselectivity, and / or production methods that use expensive and / or hazardous reagents or result in pyridinium salts containing pharmaceutically unsuitable counterions. Therefore, many known synthetic methods are not suitable for large-scale commercial synthesis.

[0008] WO 2016 / 014927 discloses a crystalline form of nicotinamide riboside chloride which is described as having advantageous properties relative to amorphous forms of nicotinamide riboside salts, such as ease of purification.

[0009] WO 2017 / 218580 discloses a synthetic method for preparing a nicotinamide riboside salt, the nicotinamide riboside salt comprising a salt containing a pharmaceutically acceptable anion. The method may include converting a pharmaceutically acceptable counterion of a nicotinamide-β-D-furanosyl moiety into another pharmaceutically acceptable counterion by ion exchange chromatography or salt exchange reaction and precipitation. In certain embodiments, the method includes converting a salt of nicotinamide riboside or an analog thereof (wherein the salt is not a chloride salt) into a corresponding chloride salt.

[0010] WO 2015 / 186068 A1 discloses the reaction of nicotinamide-β-D-ribofuranoside trifluoromethanesulfonate with sodium methoxide in an ion exchange reaction to obtain crystalline nicotinamide-β-D-riboside chloride.

[0011] CN 108774278 discloses that nicotinamide triacetyl furanose trifluoromethanesulfonate reacts with a base to deacetylate the furanose. Subsequently, the deacetylated product is treated with an acid to obtain the corresponding salt product.

[0012] However, for given applications, alternative pharmaceutically acceptable salts of nicotinamide riboside and methods that allow their preparation in an inexpensive, efficient and convenient manner are desirable.

[0013] Purpose of the Invention

[0014] Therefore, there is a need in the art for pharmaceutically acceptable nicotinamide furanoside salts, preferably crystalline salts, and methods for preparing pharmaceutically acceptable nicotinamide furanoside salts with high purity and high yield at low cost and on an industrial scale. Summary of the invention

[0015] The object is achieved by a method for preparing nicotinamide-β-D-ribofuranoside salts other than bromide and triflate by salt metathesis including counter ion exchange, using nicotinamide-β-D-ribofuranoside bromide or nicotinamide-β-D-ribofuranoside triflate as a raw material.

[0016] Nicotinamide-β-D-ribofuranoside perfluorobutylsulfonate, nicotinamide-β-D-ribofuranoside fluorosulfonate or nicotinamide-β-D-ribofuranoside perchlorate are other suitable starting materials in the process according to the invention.

[0017] In another embodiment, nicotinamide-β-D-ribofuranoside chloride or iodide is used as starting material in the process according to the invention.

[0018] In one embodiment, nicotinamide-β-D-ribofuranoside bromide and nicotinamide-β-D-ribofuranoside triflate and in particular nicotinamide-β-D-ribofuranoside iodide are preferably used as starting materials.

[0019] In a preferred embodiment, the nicotinamide-β-D-ribofuranoside salt is obtainable by the process according to the invention, wherein the salt may advantageously be provided in crystalline form.

[0020] According to a first aspect, the present invention relates to a method for preparing nicotinamide-β-D-ribofuranoside salt, comprising step (A):

[0021] (A) subjecting nicotinamide-β-D-ribofuranoside bromide, nicotinamide-β-D-ribofuranoside chloride, nicotinamide-β-D-ribofuranoside iodide, nicotinamide-β-D-ribofuranoside trifluoromethanesulfonate, nicotinamide-β-D-ribofuranoside perfluorobutylsulfonate, nicotinamide-β-D-ribofuranoside fluorosulfonate or nicotinamide-β-D-ribofuranoside perchlorate to salt metathesis including counter ion exchange to obtain a nicotinamide-β-D-ribofuranoside salt.

[0022] The nicotinamide-β-D-ribofuranoside salt prepared by this method is not a bromide, iodide, triflate, perfluorobutanesulfonate, fluorosulfonate or perchlorate.

[0023] According to a second aspect, the present invention relates to a method for preparing nicotinamide-β-D-ribofuranoside salt, comprising steps (A) and (B):

[0024] (A) Nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside bromide, nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside chloride, nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside iodide, nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside trifluoromethanesulfonate, nicotinamide-2,3 ,5-tri-O-acyl-β-D-furanosyl glycoside perfluorobutyl sulfonate, nicotinamide-2,3,5-tri-O-acyl-β-D-furanosyl glycoside fluorosulfonate or nicotinamide-2,3,5-tri-O-acyl-β-D-furanosyl glycoside perchlorate to obtain nicotinamide-2,3,5-tri-O-acyl-β-D-furanosyl glycoside salt;

[0025] (B) Deacylating nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside to obtain nicotinamide-β-D-ribofuranoside.

[0026] The nicotinamide-β-D-ribofuranoside salt prepared by this method is not a bromide, iodide, triflate, perfluorobutanesulfonate, fluorosulfonate or perchlorate.

[0027] According to a third aspect, the present invention relates to a method comprising nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside bromide, nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside chloride, nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside iodide, nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside trifluoromethanesulfonate, A method for preparing nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside salts from nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside perfluorobutylsulfonate, nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside fluorosulfonate or nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside perchlorate, comprising the step (A):

[0028] (A) Nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside bromide, nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside chloride, nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside iodide, nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside trifluoromethanesulfonate, nicotinamide-2,3 ,5-tri-O-acyl-β-D-furanosyl glycoside perfluorobutyl sulfonate, nicotinamide-2,3,5-tri-O-acyl-β-D-furanosyl glycoside fluorosulfonate or nicotinamide-2,3,5-tri-O-acyl-β-D-furanosyl glycoside perchlorate is subjected to salt metathesis including counterion exchange to obtain nicotinamide-2,3,5-tri-O-acyl-β-D-furanosyl glycoside salt.

[0029] The nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside salt prepared by this method is not a bromide, iodide, triflate, perfluorobutanesulfonate, fluorosulfonate or perchlorate.

[0030] According to a fourth aspect, the present invention relates to crystalline nicotinamide-β-D-ribofuranoside D-, L- or DL-malate; or crystalline nicotinamide-β-D-ribofuranoside D-, L- or DL-tartrate; characterized by a powder X-ray diffraction pattern, respectively.

[0031] The nicotinamide-β-D-ribofuranoside salt prepared according to the process of the invention is generally obtained in amorphous form and must, if necessary and if possible, be subsequently crystallized.

[0032] However, surprisingly, the mentioned D-, L- or DL-malic acid hydrogen salts and D-, L- or DL-tartrate hydrogen salts can be obtained directly in crystalline form with high purity and excellent yield by salt metathesis. This is very advantageous, for example, in terms of application and further processing. Therefore, it is recommended to use these salts in or as nutritional supplements. In addition, the salts can be used as raw materials for the preparation of other nicotinamide-β-D-ribofuranoside salts or related compounds.

[0033] According to a fifth aspect, the present invention relates to a nutritional supplement comprising a nicotinamide-β-D-ribofuranoside salt obtained according to the method defined in the first or second aspect or comprising a nicotinamide-β-D-ribofuranoside salt as defined in the fourth aspect.

[0034] According to a sixth aspect, the present invention relates to a pharmaceutical composition comprising a nicotinamide-β-D-ribofuranoside salt obtained according to the method defined in the first or second aspect or comprising a nicotinamide-β-D-ribofuranoside salt defined in the fourth aspect.

[0035] According to a seventh aspect, the present invention relates to a method for performing chemical synthesis, comprising the steps of (A):

[0036] (A) providing a nicotinamide-β-D-ribofuranoside salt obtained by the method defined in the first or second aspect, or providing a compound defined in the fourth aspect.

[0037] According to an eighth aspect, the present invention relates to a method for preparing nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside trifluoromethanesulfonate or iodide, the method comprising step (A):

[0038] (A) tetra-O-acyl-β-D-ribofuranose of the following formula

[0039]

[0040] wherein each R is independently selected from alkylcarbonyl, arylcarbonyl and heteroarylcarbonyl, preferably selected from C 1-10 alkylcarbonyl and benzoyl, and more preferably acetyl, and wherein R is optionally substituted independently by one or more substituents selected from the group consisting of: C 1-6 Alkyl, C 1-6 Alkoxy, C 1-6 Thioalkyl, halogen, nitro, cyano, NH(C 1-6 Alkyl), N(C 1-6 alkyl)2 and SO2N(C 1-6 Alkyl)2,

[0041] With the following formula niacinamide

[0042]

[0043] The reaction is carried out in the presence of 0.9 to 1.5 molar equivalents of trimethylsilyl trifluoromethanesulfonate or iodide relative to 1 mole of tetra-O-acyl-β-D-ribofuranose.

[0044] In a ninth aspect, the present invention relates to a compound selected from the group consisting of nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside perfluorobutylsulfonate, nicotinamide-β-D-ribofuranoside perfluorobutylsulfonate, nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside perchlorate and nicotinamide-β-D-ribofuranoside perchlorate, nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside iodide, nicotinamide-β-D-ribofuranoside iodide, nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside fluorosulfonate, and nicotinamide-β-D-ribofuranoside fluorosulfonate. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] The present invention is further described by the accompanying drawings, in which:

[0046] Figure 1 shows a powder X-ray pattern of crystalline nicotinamide-β-D-ribofuranoside D-malate hydrogen;

[0047] Figure 2 shows a powder X-ray pattern of crystalline nicotinamide-β-D-ribofuranoside L-malate hydrogen;

[0048] Figure 3 shows a powder X-ray pattern of crystalline nicotinamide-β-D-ribofuranoside DL-malate;

[0049] Figure 4 shows a powder X-ray pattern of crystalline nicotinamide-β-D-ribofuranoside D-tartrate hydrogen monohydrate;

[0050] Figure 5 shows a powder X-ray pattern of crystalline nicotinamide-β-D-ribofuranoside L-tartrate;

[0051] Figure 6 shows a powder X-ray pattern of crystalline nicotinamide-β-D-ribofuranoside DL-tartrate;

[0052] Figure 7 shows a powder X-ray pattern of crystalline nicotinamide-2,3,5-O-triacetyl-β-D-ribofuranoside L-tartrate;

[0053] Figure 8 shows a powder X-ray pattern of crystalline nicotinamide-2,3,5-O-triacetyl-β-D-ribofuranoside D-tartrate;

[0054] Fig. 9 shows a powder X-ray pattern of crystalline anhydrous nicotinamide-β-D-ribofuranoside D-tartrate;

[0055] {x-axis: position [° 2θ] (copper (Cu); y-axis: counts)}, respectively. DETAILED DESCRIPTION

[0056] Various aspects of the invention will now be described in more detail with reference to the accompanying drawings.

[0057] First, second and third aspects: Method according to the invention

[0058] According to a first aspect, the invention relates to a method for preparing a salt metathesis with an anion Y comprising counter ion exchange. - Replace the anion X in the following compound - =Br - , Cl - ,I - CF3SO3 - (trifluoromethanesulfonate ion), n-C4F9SO3 - (perfluorobutanesulfonate ion), FSO3 - or ClO4 - Methods

[0059]

[0060] Therefore, in a first aspect, the present invention relates to a method for preparing nicotinamide-β-D-ribofuranoside salt, which comprises the step (A):

[0061] (A) subjecting nicotinamide-β-D-ribofuranoside bromide, chloride, iodide, triflate, perfluorobutanesulfonate, fluorosulfonate or perchlorate to salt metathesis including counterion exchange to obtain nicotinamide-β-D-ribofuranoside salt.

[0062] In another embodiment, according to the second aspect, nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside bromide, chloride, iodide, triflate, perfluorobutylsulfonate, fluorosulfonate or perchlorate of the formula

[0063] Br - , Cl - ,I - CF3SO3 - 、n-C4F9SO3 - 、FSO3 - or ClO4 - Salt metathesis is performed to react with anions Y - Exchange Br- , Cl - ,I - CF3SO3 - 、n-C4F9SO3 - FSO3 - or ClO4 - Subsequently, the acyl group is cleaved to provide the desired nicotinamide-β-D-ribofuranoside salt.

[0064] Therefore, in a second aspect, the present invention relates to a method for preparing nicotinamide-β-D-ribofuranoside salt, comprising steps (A) and (B):

[0065] (A) subjecting nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside bromide, chloride, iodide, triflate, perfluorobutanesulfonate, fluorosulfonate or perchlorate to salt metathesis including counterion exchange to obtain nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside salt; and

[0066] (B) Deacylating nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside to obtain nicotinamide-β-D-ribofuranoside.

[0067] If desired, the nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside salt obtained in step (A) may be used for a purpose different from that of step (B).

[0068] Therefore, in a third aspect, the present invention relates to a method for preparing nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside salt, which comprises the step (A):

[0069] (A) subjecting nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside bromide, chloride, iodide, triflate, perfluorobutanesulfonate, fluorosulfonate or perchlorate to salt metathesis including counterion exchange to obtain nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside salt.

[0070] Nicotinamide-β-D-ribofuranoside bromide [N1-(β-D-ribofuranosyl)-3-aminocarbonylpyridinium bromide]

[0071]

[0072] As used in step (A) of the method defined in the first aspect, is a well-known compound (CAS No. 78687-39-5). For example, Lee et al. disclosed its chemical synthesis method (Chem. Commun., 1999, 729-730). Another synthesis method is disclosed in EP 18173208.2 which has not been published on the filing date of the present application.

[0073] The reference also discloses the preparation of nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside bromide as a precursor of nicotinamide-β-D-ribofuranoside bromide.

[0074] Nicotinamide-β-D-ribofuranoside trifluoromethanesulfonate [N1-(β-D-ribofuranosyl)-3-aminocarbonylpyridine trifluoromethanesulfonate]

[0075]

[0076] It is also a well-known compound (CAS No. 445489-49-6).

[0077] Nicotinamide-β-D-ribofuranoside trifluoromethanesulfonate and nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside trifluoromethanesulfonate can be prepared by the following method: nicotinamide is reacted with tetra-O-acyl-β-D-ribofuranose in acetonitrile in the presence of trimethylsilyl trifluoromethanesulfonate (TMSOTf) to obtain nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside trifluoromethanesulfonate. The acyl group can then be cleaved according to known methods to give nicotinamide-β-D-ribofuranoside trifluoromethanesulfonate (e.g., Makarova et al.: “Syntheses and chemical properties of β-nicotinamide riboside and its analogues and derivatives”, Beilstein J Org Chem 2019, 15: 401-430; Tanimori et al., “An Efficient Chemical Synthesis of Nicotinamide Riboside (NAR) and Analogues”, Bioorganic & Medicinal Chemistry Letters 12 (2002) 1135–1137).

[0078] Nicotinamide-β-D-ribofuranoside perfluorobutylsulfonate and nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside perfluorobutylsulfonate, nicotinamide-β-D-ribofuranoside perchlorate and nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside perchlorate can be prepared by the following methods: nicotinamide is reacted with tetra-O-acyl-β-D-ribofuranoside in a solvent such as acetonitrile in the presence of trimethylsilyl perfluorobutylsulfonate (CAS No. 68734-62-3) and trimethylsilyl perchlorate (CAS No. 18204-79-0) to obtain nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside perfluorobutylsulfonate and perchlorate, respectively. The acyl group can then be cleaved according to known methods to obtain nicotinamide-β-D-ribofuranoside perfluorobutyl sulfonate and perchlorate, respectively.

[0079] Nicotinamide-β-D-ribofuranoside chloride and nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside chloride, nicotinamide-β-D-ribofuranoside iodide and nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside iodide, nicotinamide-β-D-ribofuranoside fluorosulfonate and nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside fluorosulfonate can be prepared by the following methods, respectively. Preparation: Nicotinamide is reacted with tetra-O-acyl-β-D-ribofuranose in a solvent such as acetonitrile in the presence of trimethylsilyl chloride (CAS No. 75-77-4), trimethylsilyl iodide (CAS No. 16029-98-4), and trimethylsilyl fluorosulfonate (CAS No. 3167-56-4) to obtain nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranose chloride, iodide, and fluorosulfonate, respectively. The acyl group can then be cleaved according to known methods to obtain nicotinamide-β-D-ribofuranose chloride, iodide, and fluorosulfonate, respectively.

[0080] The term “salt metathesis” as used in this disclosure is synonymous with terms such as “double replacement reaction,” “double displacement reaction,” or “metathesis reaction.” Salt metathesis is a known technique for exchanging counterions between two different salts.

[0081] Thus, step (A) defines a reaction in which a cation comprising Cat is used. + and anion Y - A suitable second salt for the first salt, for example nicotinamide-β-D-ribofuranoside salt NR + Br -(or Nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside salt AcONR + Br - ) to perform salt metathesis to exchange the counter ion, i.e., to use Y - Exchange NR + Br - (or AcONR + Br - ) - , obtain nicotinamide-β-D-furanosyl glycoside salt NR + Y - (or AcONR + Y - ) and Cat + Br - . The reaction is summarized by the following equation:

[0082] NR + Br - (or AcONR + Br - )+Cat + Y - →NR + Y - (or AcONR + Y - )+Cat + Br -

[0083] For example, the driving force for the salt metathesis reaction in the above equation can be the formation of a more stable salt and the removal of products from the chemical equilibrium of the reaction, for example by making the formed NR + Y - (AcONR + Y - ) or Cat + Br - Therefore, in order to drive the reaction to the product, the educts must be selected according to their solubility in each other or in the solvent and the energetically favorable conditions.

[0084] Similar mechanisms apply to the reactions of chlorides, iodides, triflates, perfluorobutanesulfonates, fluorosulfonates, and perchlorates.

[0085] If the salt metathesis reaction is carried out in a solvent, its effect on the reaction will be described below accordingly. Solvents section in more detail.

[0086] The term "salt metathesis" as used herein does not mean that the anion of β-nicotinamide riboside is exchanged for another anion by ion exchange using an ion exchanger. Therefore, the process defined in step (A) does not include anion exchange by an ion exchanger.

[0087] However, this process does not exclude the use of an ion exchanger in any reaction step before step (A) or after step (A).

[0088] Nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside bromide, nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside chloride, nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside iodide, nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside trifluoromethanesulfonate, nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside perfluorobutylsulfonate, nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside fluorosulfonate or nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside perchlorate used in step (B) of the method according to the second aspect is known or can be prepared according to a known method.

[0089] The term "acyl" used in conjunction with nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside salts, i.e., bromide, chloride, iodide, triflate, perfluorobutanesulfonate, fluorosulfonate or perchlorate, means that the acyl group is independently selected from alkylcarbonyl, arylcarbonyl and heteroarylcarbonyl, preferably selected from C 1-10 alkylcarbonyl and benzoyl, more preferably acetyl, and wherein R is optionally substituted independently by one or more substituents selected from the group consisting of: C 1-6 Alkyl, C 1-6 Alkoxy, C 1-6 Thioalkyl, halogen, nitro, cyano, NH(C 1-6 Alkyl), N(C 1-6 alkyl)2 and SO2N(C 1-6 Alkyl)2.

[0090] In one embodiment, the nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside salt obtained in step (A) may be isolated and purified before deacylation in step (B).

[0091] In another embodiment, the nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside salt is not purified prior to deacylation in step (B).

[0092] The deacylation (deprotection) according to step (B) can be carried out according to methods known in the art, for example, by subjecting the salt obtained in step (A) to an acid such as hydrogen bromide, hydrogen chloride, hydrogen iodide or sulfuric acid, or a base such as ammonia.

[0093] According to a preferred embodiment of the first, second and third aspects: nicotinamide-β-D-ribofuranoside bromide, chloride chloride, iodide, triflate, perfluorobutylsulfonate, fluorosulfonate or perchlorate or nicotinamide-2,3,5-trifluoromethanesulfonate O-Acyl-β-D-ribofuranoside bromide, chloride, iodide, trifluoromethanesulfonate, perfluorobutylsulfonate, fluorosulfonic acid Salt or perchlorate is used as a starting material in step (A)

[0094] According to the present invention, the nicotinamide-β-D-ribofuranoside salt or nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside salt used in step (A) is bromide, chloride, iodide, trifluoromethanesulfonate, perfluorobutylsulfonate, fluorosulfonate or perchlorate. Bromide and trifluoromethanesulfonate are easily modified compounds, and therefore are used as raw materials for many subsequent process steps in the art.

[0095] Furthermore, at least nicotinamide-β-D-ribofuranoside bromide or nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside bromide or nicotinamide-β-D-ribofuranoside chloride or nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside chloride can be provided in crystalline form, which is advantageous with regard to the preparation of further crystalline nicotinamide-β-D-ribofuranoside salts due to their purity.

[0096] In a preferred embodiment, the method for preparing nicotinamide-β-D-ribofuranoside bromide or nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside bromide disclosed in EP 18173208.2 (not yet published at the filing date of the present application) is used. This reference is incorporated herein in its entirety.

[0097] Therefore, in one embodiment of the first aspect, the method according to the invention comprises steps (X) and (Y) before step (A) and step (Z):

[0098] (X) tetra-O-acyl-β-D-ribofuranose of the following formula

[0099]

[0100] Reaction with hydrogen bromide in acetic acid gives tri-O-acyl-D-furanosyl bromide (as a mixture of β- and α-anomers) of the formula

[0101]

[0102] (Y) reacting tri-O-acyl-D-ribofuranoside bromide with nicotinamide

[0103]

[0104] Nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside bromide of the following formula is obtained:

[0105] and

[0106] (Z) deacylation of the nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside bromide obtained in step (Y) by removing the R group using hydrogen bromide in acetic acid to obtain nicotinamide-β-D-ribofuranoside bromide of the formula

[0107]

[0108] The nicotinamide-β-D-ribofuranoside bromide obtained in step (Z) is used in step (A).

[0109] Basically, in other embodiments, an acid other than HBr or a base such as ammonia in acetic acid can be used for the deacylation step (Z).

[0110] The nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside bromide obtained in step (Y) is usually obtained by mixing with the α-anomer. For example, the molar ratio β:α may be about 85:15.

[0111] Therefore, in one embodiment, if there is no purification at the mixed stage of the β- and α-anomers, in the subsequent steps the isolate is also provided as a mixture of β- and α-anomers. Purification can produce a pure β-anomer.

[0112] In another embodiment, nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside bromide can be purified to produce the pure β-anomer before it is subjected to acyl cleavage.

[0113] According to another embodiment of the first aspect, the present invention relates to a method comprising steps (X) and (Y) before step (A):

[0114] (X) tetra-O-acyl-β-D-ribofuranose of the following formula

[0115]

[0116] wherein each R is independently selected from alkylcarbonyl, arylcarbonyl and heteroarylcarbonyl, preferably selected from C 1-10 alkylcarbonyl and benzoyl, and more preferably acetyl, and wherein R is optionally substituted independently by one or more substituents selected from the group consisting of: C 1-6 Alkyl, C 1-6 Alkoxy, C 1-6 Thioalkyl, halogen, nitro, cyano, NH(C1-6 Alkyl), N(C 1-6 alkyl)2 and SO2N(C 1-6 Alkyl)2,

[0117] Reaction with nicotinamide in the presence of trimethylchlorosilane, trimethylbromosilane, trimethyliodosilane, trimethylsilyl trifluoromethanesulfonate, trimethylsilyl perfluorobutylsulfonate, trimethylsilyl fluorosulfonate or trimethylsilyl perchlorate

[0118]

[0119] Nicotinamide-2,3,5-tri-O-acyl-β-D-furanosyl glycoside chloride, bromide, iodide, trifluoromethanesulfonate, perfluorobutylsulfonate, fluorosulfonate or perchlorate of the following formula are obtained respectively:

[0120] Cl - Br - ,I - CF3SO3 - 、n-4F9SO3 - 、FSO3 - or ClO4 - ;

[0121] (Y) deacylating the nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside chloride, bromide, iodide, triflate, perfluorobutylsulfonate or perchlorate obtained in step (X) by removing the R group to obtain a nicotinamide-β-D-ribofuranoside chloride, bromide, iodide, triflate, perfluorobutylsulfonate, fluorosulfonate or perchlorate compound of the formula

[0122] Cl - Br - ,I - CF3SO3 - 、n-C4F9SO3 - 、FSO3 - or ClO4 - ,

[0123] The chloride, bromide, iodide, triflate, perfluorobutanesulfonate, fluorosulfonate or perchlorate of nicotinamide-β-D-ribofuranoside formed in step (Y) is used in step (A).

[0124] In one embodiment of the second aspect, the method according to the invention comprises steps (X) and (Y) before step (A):

[0125] (X) tetra-O-acyl-β-D-ribofuranose of the following formula

[0126]

[0127] Reaction with hydrogen bromide in acetic acid gives tri-O-acyl-D-ribofuranoside bromide (as a mixture of β- and α-anomers) of the formula

[0128]

[0129] (Y) reacting tri-O-acyl-D-ribofuranoside bromide with nicotinamide

[0130]

[0131] Nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside bromide of the following formula is obtained:

[0132]

[0133] The nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside bromide obtained in step (Y) is used in step (A).

[0134] The product obtained in step (Y) may also be used in the process defined in the third aspect.

[0135] R is an acyl group independently selected from alkylcarbonyl, arylcarbonyl and heteroarylcarbonyl, preferably selected from C 1-10 alkylcarbonyl and benzoyl, and more preferably acetyl, and wherein R is optionally substituted independently by one or more substituents selected from the group consisting of: C 1-6 Alkyl, C 1-6 Alkoxy, C 1-6 Thioalkyl, halogen, nitro, cyano, NH(C 1-6 Alkyl), N(C 1-6 alkyl)2 and SO2N(C 1-6 Alkyl)2.

[0136] The term "acyl" used synonymously with the term "acyl group" in nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside bromide means that the acyl group may be independently selected from alkylcarbonyl, arylcarbonyl or heteroarylcarbonyl.

[0137] The term "alkylcarbonyl" is used synonymously with the term "alkanoyl."

[0138] In one embodiment, R is independently selected from alkylcarbonyl, arylcarbonyl and heteroarylcarbonyl, preferably selected from C 1-10 alkylcarbonyl and benzoyl, and preferably acetyl.

[0139] In one embodiment, the acyl group may be substituted.

[0140] In one embodiment, the acyl group may be independently substituted with one or more of the following substituents: 1-6 Alkyl, C 1-6 Alkoxy, C 1-6 Thioalkyl, halogen, nitro, cyano, NH(C 1-6 Alkyl), N(C 1-6 alkyl)2 and SO2N(C 1-6 Alkyl)2.

[0141] In one embodiment, the acyl group is C 1-6 Alkanoyl, such as formyl, acetyl, propionyl, butyryl, valeryl or cyclohexyl, is optionally substituted with one or more of the substituents mentioned above.

[0142] In another embodiment, acyl is benzoyl or naphthoyl, preferably benzoyl, optionally substituted with one or more substituents as mentioned above.

[0143] Tetra-O-acyl-β-D-ribofuranose is a known compound or can be prepared according to a known method.

[0144] In a preferred embodiment, commercially available tetra-O-acetyl-β-D-ribofuranose (CAS No. 13035-61-5)

[0145]

[0146] Used in step (X) to give 2,3,5-tri-O-acyl-D-ribofuranoside bromide.

[0147] The nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside bromide obtained in step (Y) is usually produced in the form of an anomeric mixture, such as a mixture of anomers β and α, such as a β:α ratio of about 5:1 to 6:1.

[0148] In one embodiment, crude nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside bromide can be used in step (A) of the method according to the second aspect, i.e. it can be subjected to salt metathesis. The salt formed is then deacylated according to step (B) to obtain the desired nicotinamide-β-D-ribofuranoside salt.

[0149] In another embodiment, crude nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside bromide can be used in step (Z) to obtain nicotinamide-β-D-ribofuranoside bromide by deacylation. Nicotinamide-β-D-ribofuranoside bromide can then be used in step (A) of the method according to the first aspect to obtain the desired nicotinamide-β-D-ribofuranoside salt by salt metathesis.

[0150] In another embodiment, it may be advantageous to purify and crystallize the crude nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside bromide obtained in step (Y) prior to step (Z). The use of purified and crystallized nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside bromide in the deacylation (deprotection) step according to step (Z) may improve the tendency of nicotinamide-β-D-ribofuranoside bromide to crystallize and thus be in substantially pure form.

[0151] Preferably, the nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside bromide obtained in step (Y) can be recrystallized from acetone to obtain a pure β-anomer.

[0152] Therefore, in one embodiment, the method further comprises the step (Y1):

[0153] (Y1) Purification of the product obtained in step (Y).

[0154] Preferably, the purification according to step (Y1) is crystallization or recrystallization.

[0155] The yields of steps (X), (Y) and (Y1) are generally in the range of 40% to 50%.

[0156] In one embodiment, the purified nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside bromide can be used in step (A) defined in the second aspect, i.e., it can be subjected to salt metathesis. The formed salt is then deacylated according to step (B) to obtain the desired nicotinamide-β-D-ribofuranoside salt.

[0157] In another embodiment, the purified nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside bromide can be deacylated to obtain nicotinamide-β-D-ribofuranoside bromide, which can be used in step (A) of the method according to the first aspect to obtain the desired nicotinamide-β-D-ribofuranoside salt by salt metathesis.

[0158] If step (A) defined in the first aspect is to be carried out, the acyl group in the nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside bromide obtained in step (Y) or (Y1) must be cleaved, ie the protected hydroxyl group must be deprotected.

[0159] Essentially any method known in the art may be used to remove the acyl group from the protected OH-group. The cleavage may advantageously be carried out with hydrogen bromide in acetic acid.

[0160] The reaction can also be carried out advantageously on a large scale.

[0161] Nicotinamide-β-D-ribofuranoside bromide is usually precipitated in the form of crystals directly from the solution obtained in the deprotection step.

[0162] Crystalline nicotinamide-β-D-ribofuranoside bromide can be obtained with a purity of more than 97%, i.e., it contains almost no α-anomer and only a small amount of nicotinamide, which has been used to replace the bromine in tri-O-acyl-β-D-ribofuranoside bromide and to neutralize excess hydrogen bromide.

[0163] If further necessary, nicotinamide-β-D-ribofuranoside bromide can be further purified, preferably by recrystallization. A suitable solvent is, for example, methanol.

[0164] In a preferred embodiment, the method further comprises the step (Z1):

[0165] (Z1) Purification of the product obtained in step (Z).

[0166] In a preferred embodiment, the purification according to step (Z1) comprises either crystallization or recrystallization.

[0167] The yields of steps (Z) and (Z1) are generally in the range of 60% to 70%.

[0168] Advantageously, other salts, preferably crystalline salts, in which the anion is preferably a pharmaceutically acceptable anion can be prepared according to the process of the invention starting from the bromide or triflate by salt metathesis.

[0169] Preferably, nicotinamide-β-D-ribofuranoside hydrogen malate and nicotinamide-β-D-ribofuranoside hydrogen tartrate, and their 2,3,5-O-triacyl compounds can be synthesized, preferably in crystalline form.

[0170] In another embodiment of the second aspect, the invention relates to a method comprising step (X) prior to step (A):

[0171] (X) tetra-O-acyl-β-D-ribofuranose of the following formula

[0172]

[0173] wherein each R is independently selected from alkylcarbonyl, arylcarbonyl and heteroarylcarbonyl, preferably selected from C 1-10 alkylcarbonyl and benzoyl, and more preferably acetyl, and wherein R is optionally substituted independently by one or more substituents selected from the group consisting of: C 1-6 Alkyl, C 1-6 Alkoxy, C 1-6 Thioalkyl, halogen, nitro, cyano, NH(C 1-6 Alkyl), N(C 1-6 alkyl)2 and SO2N(C 1-6 Alkyl)2,

[0174] Reaction with nicotinamide in the presence of trimethylchlorosilane, trimethylbromosilane, trimethyliodosilane, trimethylsilyl trifluoromethanesulfonate, trimethylsilyl perfluorobutylsulfonate, trimethylsilyl fluorosulfonate or trimethylsilyl perchlorate

[0175]

[0176] Nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside chloride, bromide, iodide, trifluoromethanesulfonate, perfluorobutylsulfonate, fluorosulfonate or perchlorate of the formula

[0177] Cl - Br - ,I - CF3SO3 - 、n-C4F9SO3 - 、FSO3 - or ClO4 - ;

[0178] wherein the chloride, bromide, iodide, triflate, perfluorobutanesulfonate, fluorosulfonate or perchlorate of nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside formed in step (X) is used in step (A).

[0179] Pharmaceutically acceptable ions

[0180] Preferably, in step (A) the + Y - The counter ion Y of the salt obtained by counter ion exchange - It is a pharmaceutically acceptable ion.

[0181] As used herein, the term "pharmaceutically acceptable ions" includes ions selected from the group consisting of:

[0182] Inorganic ions; or

[0183] Carboxylate, wherein the carboxylate is derived from a carboxylic acid, optionally independently selected from carboxyl, hydroxyl, thio, keto, amino, mono-C 1-6 Alkyl, hydroxyl C 1-6 Alkylene and di(C 1-6 substituted with one or more substituents from the group consisting of alkyl)amino; or

[0184] C 1-12 Alkyl sulfonate; or

[0185] Arylsulfonate, wherein the aryl moiety is optionally independently selected from carboxyl, hydroxyl, amino, mono-C 1-6 Alkyl and di(C 1-6 alkyl)amino, halogen, C 1-6 The alkyl group is substituted with one or more substituents;

[0186] and wherein the pharmaceutically acceptable salt is not a bromide or an iodide or a triflate or a perfluorobutanesulfonate or a fluorosulfonate or a perchlorate.

[0187] In a preferred embodiment,

[0188] the inorganic ion is selected from the group consisting of chloride, bisulfate, sulfate, dihydrogen phosphate, monohydrogen phosphate, phosphate, nitrate, bicarbonate and carbonate;

[0189] The carboxylate is selected from the group consisting of formate, acetate, oxalate, malonate, succinate, fumarate, maleate, citrate, malate, tartrate, ascorbate, glucuronide, alpha-ketoglutarate, benzoate and salicylate;

[0190] C 1-12 Alkyl sulfonate is selected from the group consisting of methanesulfonate and camphorsulfonate;

[0191] The aryl sulfonate is selected from the group consisting of benzene sulfonate and toluene sulfonate.

[0192] In a preferred embodiment, the pharmaceutically acceptable ion is malate.

[0193] In a particularly preferred embodiment, the pharmaceutically acceptable ion is hydrogen malate.

[0194] The term "hydrogenmalate" refers to a monocarboxylic acid radical.

[0195] In a further particularly preferred embodiment, the hydrogen malate is the D-, L- or DL-stereoisomer.

[0196] In a further preferred embodiment, the pharmaceutically acceptable anion is tartrate.

[0197] In a particularly preferred embodiment, the pharmaceutically acceptable anion is bitartrate.

[0198] The term "tartrate" refers to a monocarboxylate.

[0199] In a further particularly preferred embodiment, the bitartrate ion is the D-, L- or DL-stereoisomer.

[0200] Particular preference is given to preparing the D-, L- or DL-stereoisomers of hydrogen malate or hydrogen tartrate, since the process according to the invention affords these compounds in high yield and crystallinity, which is particularly advantageous with regard to handling and further processing of the salts.

[0201] Frequently, crystalline compounds have been obtained directly in salt metathesis reactions.

[0202] This is advantageous compared to counterion exchange, for example by means of ion exchangers, in which the compounds are usually obtained in amorphous form and have to be crystallized in a subsequent step.

[0203] With pharmaceutically acceptable ion Y - Related cations Cat + Nicotinamide-β-D-ribofuranoside bromide, Chloride, iodide, triflate, perfluorobutanesulfonate, fluorosulfonate, or perchlorate or nicotinamide-2,3,5- Tri-O-acyl-β-D-ribofuranoside bromide, chloride, iodide, trifluoromethanesulfonate, perfluorobutylsulfonate, fluorosulfonate Salt double decomposition of acid salt or perchlorate

[0204] Nicotinamide-β-D-ribofuranoside bromide, chloride, iodide, triflate, perfluorobutylsulfonate, fluorosulfonate or perchlorate or nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside bromide, chloride, iodide, triflate, perfluorobutylsulfonate, fluorosulfonate or perchlorate can be subjected to salt metathesis using essentially any salt having a pharmaceutically acceptable anion.

[0205] Although not limited, the cation Cat used in combination with a pharmaceutically acceptable anion + Preferably it is derived from an ammonium salt or a phosphonium salt.

[0206] Preferably, in one embodiment, the cation of the salt is [NR 1 R 2 R 3 R 4 ] + , where R 1 , R 2 , R 3 and R 4 Independently selected from H, C 1-12 Alkyl and aryl groups are optionally substituted.

[0207] In one embodiment, the cation of the salt is NH4 + .

[0208] In a preferred embodiment, the cation of the salt is derived from a primary ammonium salt, i.e., the cation of the salt is [NR 1 H3] + , where R 1 Selected from C 1-12 Alkyl and aryl groups are optionally substituted.

[0209] In another preferred embodiment, the cation of the salt is derived from a secondary ammonium salt, i.e., the cation of the salt is [NR 1 R 2 H2] + , where R 1 and R 2 Independently selected from C 1-12 Alkyl and aryl groups are optionally substituted.

[0210] In a further preferred embodiment, [NR 1 R 2 R 3 R 4 ] + R 1 , R 2 , R 3 and R 4 One of them is H. Therefore, the cation of the salt is derived from a tertiary ammonium salt, that is, the cation of the salt is [NR 1 R 2 R 3 H] + , where R 1 , R 2 and R 3 Independently selected from C 1-12 Alkyl and aryl groups are optionally substituted.

[0211] In yet another preferred embodiment, the cation is a quaternary ammonium salt. Thus, the cation of the salt is [NR 1 R 2 R 3 R 4 ] + , where R 1 , R 2 , R 3 and R 4 Independently selected from C 1-12 Alkyl and aryl groups are optionally substituted.

[0212] In a preferred embodiment, [NR 1 R 2 R 3 R 4 ] + is [N(C2H5)4] + or [N(C4H9)4] +.

[0213] In a further preferred embodiment, R 1 , R 2 , R 3 and R 4 One of them is benzyl.

[0214] In another embodiment, the cation of the salt is derived from an N-heterocyclic aromatic system or an N-alkylated heterocyclic aromatic system, such as pyridine or N-methylpyridine.

[0215] In another embodiment, the cation of the salt is [PR 1 R 2 R 3 R 4 ] + , where R 1 , R 2 , R 3 and R 4 Independently selected from H, C 1-12 Alkyl and aryl groups are optionally substituted.

[0216] In a further preferred embodiment, [PR 1 R 2 R 3 R 4 ] + R 1 , R 2 , R 3 and R 4 One of them is H.

[0217] It is also conceivable to use lithium or sodium salts comprising pharmaceutically acceptable anions in the salt metathesis reaction according to the invention.

[0218] Suitable salts are commercially available or can be prepared according to known methods, for example by reacting triethylamine or tributylamine or tetraethylammonium hydroxide or tetrabutylammonium hydroxide or benzyltrimethylammonium hydroxide with an acid such as sulfuric acid or a carboxylic acid such as malic acid or tartaric acid in a molar ratio allowing the preparation of mono- or divalent anions.

[0219] Solvents

[0220] The salt metathesis can be carried out in the absence of a solvent, ie by salt metathesis of a solid nicotinamide-β-D-ribofuranoside salt or a solid nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside salt with, for example, a liquid salt.

[0221] In a preferred embodiment, the salt metathesis in step (A) is carried out in the presence of a solvent.

[0222] The following non-limiting embodiments I, II, III or IV for carrying out the above-mentioned salt metathesis reaction are preferred:

[0223] Embodiment I: Selecting a solvent so that NR + Br - (or AcONR + Br - ) and Cat + Y - are all soluble in the solvent, however, the NR obtained in step (A) + Y - (or AcONR + Y - ) is insoluble in the solvent and precipitates, while Cat + Br - is soluble. NR can then be separated by filtration + Y - (or AcONR + Y - ).

[0224] Embodiment II: Selecting a solvent so that NR + Br - (or AcONR + Br - ) and Cat + Y - are all soluble in the solvent, however, the NR obtained in step (A) + Y - (or AcONR + Y - ) is soluble in the solvent, while Cat + Br - NR can then be separated from the supernatant, for example, according to known techniques. + Y - (or AcONR + Y - ).

[0225] Embodiment III: Selecting a solvent such that the NR obtained in step (A) + Br - and NR + Y - (or AcONR + Br - and AcONR + Y - ) is insoluble in the solvent, while Cat + Br - and Cat + Y -NR can then be separated, for example, by filtration + Y - (or AcONR + Y - ).

[0226] Embodiment IV: Selecting a solvent such that the NR obtained in step (A) + Br - and NR + Y - (or AcONR + Br - and AcONR + Y - ) is soluble in the solvent, while Cat + Br - and Cat + Y - NR can then be separated from the supernatant, for example, according to known techniques. + Y - (or AcONR + Y - ).

[0227] In addition to NR + Br - and AcONR + Br - In addition, NR + Cl - and AcONR + Cl - NR + I - and AcONR + I - NR + CF3SO3 - and AcONR + CF3SO3 - or NR + n-C4F9SO3 - and AcONR + n-C4F9SO3 - , NR + FSO3 - and AcONR + FSO3 - or NR + ClO4 - and AcONR + ClO4 - .

[0228] Therefore, by appropriately selecting the solvent used in the salt metathesis reaction defined in step (A), i.e. by determining a solubility diagram, the outcome of the salt metathesis reaction can be predicted. Such a solubility diagram can be determined by a person skilled in the art by routine experimentation.

[0229] Embodiment 1 provides good results, provided that Cat + Y - is an ammonium salt or a phosphonium salt as defined above, preferably an ammonium salt.

[0230] In a further preferred embodiment, embodiment 1 provides good results provided that alcohol is used as solvent, or the solvent comprises alcohol, and Cat + Y - Preferred are ammonium salts or phosphonium salts as defined above, preferably ammonium salts.

[0231] Preferably, the alcohol used for the salt metathesis is selected from the group consisting of methanol, ethanol, propanol or butanol, or a mixture of two or more thereof, optionally the alcohol or the mixture comprises water.

[0232] The inventors of the present invention have surprisingly discovered that the formed nicotinamide-β-D-ribofuranoside and nicotinamide-triacyl-O-β-D-ribofuranoside salts provide an unusually high solubility difference compared to the nicotinamide-β-D-ribofuranoside bromide, chloride, iodide, triflate, perfluorobutylsulfonate, fluorosulfonate or perchlorate salts and nicotinamide-tri-O-acyl-β-D-ribofuranoside bromide, chloride, iodide, triflate, perfluorobutylsulfonate, fluorosulfonate or perchlorate salts, respectively, used for salt metathesis in specific alcohols, making it the method of choice under the reaction conditions of specific embodiment I.

[0233] Preferably, in step (A), a saturated solution of nicotinamide-β-D-ribofuranoside bromide, chloride, iodide, triflate, perfluorobutylsulfonate, fluorosulfonate or perchlorate or nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside bromide, chloride, iodide, triflate, perfluorobutylsulfonate, fluorosulfonate or perchlorate in one or more alcohols as defined above, optionally including water, and a suitable ammonium salt or phosphonium salt are combined with one another, wherein step (A) is carried out, i.e. the nicotinamide-β-D-ribofuranoside salt or nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside salt produced by counterion exchange is precipitated and can be separated by filtration.

[0234] The term "saturated solution" refers in a preferred embodiment to the preparation of NR + Br - (or AcONR + Br -) and Cat + Y - The concentrated solution is prepared so that the solubility limit at 23°C is not exceeded.

[0235] The term "saturated solution" refers in another preferred embodiment to the preparation of NR + Br - NR + Cl - NR + I - NR + CF3SO3 - NR + n-C4F9SO3 - NR + FSO3 - or NR + ClO4 - (or AcONR + Br - ,AcONR + Cl - ,AcONR + I - ,AcONR + CF3SO3 - ,AcONR + n-C4F9SO3 - ,AcONR + FSO3 - AcONR + ClO4 - ) and Cat + Y - The concentrated solution is prepared so that the solubility limit at 23°C is not exceeded.

[0236] Preferably, the salt metathesis reaction according to step (A) is carried out at ambient temperature, ie in the range of 5 to 60°C, preferably 10 to 40°C.

[0237] Obviously, the salt metathesis reaction defined in step (A) is not limited to ammonium or phosphonium salts and the alcohols defined above.

[0238] In a preferred embodiment, the present invention relates to a method for preparing nicotinamide-β-D-ribofuranoside salt or nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside salt, wherein step (A) defined in the first and second aspects at least comprises steps (A1) and (A2):

[0239] (A1) NH3 or NR 1 H2 or NR 1 R 2 H or NR 1 R2 R 3 or [NR 1 R 2 R 3 R 4 ]OH is reacted with an acid preferably containing a pharmaceutically acceptable anion to give the respective ammonium salts, wherein R 1 , R 2 , R 3 and R 4 Independently selected from C 1-12 Alkyl and aryl groups are optionally substituted.

[0240] (A2) reacting a nicotinamide-β-D-ribofuranoside bromide, chloride, iodide, triflate, perfluorobutylsulfonate, fluorosulfonate or perchlorate salt or a nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside bromide, chloride, iodide, triflate, perfluorobutylsulfonate, fluorosulfonate or perchlorate salt with the ammonium salt from step (A1) to perform a salt metathesis including counterion exchange to obtain a nicotinamide-β-D-ribofuranoside salt or a nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside salt, wherein acyl has the meaning defined above.

[0241] In a preferred embodiment, NR is used in step (A1). 1 R 2 R 3 or [NR 1 R 2 R 3 R 4 ]OH.

[0242] Likewise, in another embodiment, the present invention relates to a method for preparing a nicotinamide-β-D-ribofuranoside salt or a nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside salt, the method comprising:

[0243] (A1) Make PH3 or PR 1 H2 or PR 1 R 2 H or PR 1 R 2 R 3 or [PR 1 R 2 R 3 R 4 ]OH reacts with an acid to give the respective phosphonium salts, where R 1 , R 2 , R 3 and R 4 Independently selected from C 1-12 Alkyl and aryl groups are optionally substituted.

[0244] (A2) reacting a nicotinamide-β-D-ribofuranoside bromide, chloride, iodide, triflate, perfluorobutylsulfonate, fluorosulfonate or perchlorate salt or a nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside bromide, chloride, iodide, triflate, perfluorobutylsulfonate, fluorosulfonate or perchlorate salt with the phosphonium salt from step (A0) to perform a salt metathesis including counterion exchange to obtain a nicotinamide-β-D-ribofuranoside salt or a nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside salt, wherein acyl has the meaning defined above.

[0245] In a preferred embodiment, PR is used in step (A1). 1 R 2 R 3 or [PR 1 R 2 R 3 R 4 ]OH.

[0246] Further purification

[0247] If necessary, the product obtained in step (A) or step (B) can be purified according to known methods to obtain pure β-anomer.

[0248] In one embodiment, the product may be recrystallized.

[0249] In another embodiment, the product may be dissolved in a suitable solvent and then precipitated by adding a solvent in which the product is insoluble.

[0250] Therefore, the method defined in the first, second or third aspect further comprises step (c):

[0251] (C) purifying the salt obtained in step (A) or (B), preferably by crystallization.

[0252] In one embodiment, the process according to the invention can start in step (A) with the pure β-anomer, i.e. pure nicotinamide-β-D-ribofuranoside bromide, chloride, iodide, triflate, perfluorobutanesulfonate, fluorosulfonate or perchlorate or pure nicotinamide-2,3,5-O-triacyl-β-D-ribofuranoside bromide, chloride, iodide, triflate, perfluorobutanesulfonate, fluorosulfonate or perchlorate.

[0253] The term "pure" means that nicotinamide-β-D-furanoside bromide, chloride, iodide, triflate, perfluorobutylsulfonate, fluorosulfonate or perchlorate or nicotinamide-2,3,5-O-triacyl-β-D-ribofuranoside bromide, chloride, iodide, triflate, perfluorobutylsulfonate, fluorosulfonate or perchlorate may contain up to 5% of the α-anomer.

[0254] In one embodiment, the salt is provided in isolated form, optionally purified, prior to use in step (A).

[0255] In another embodiment, the process can start in step (A) with the β-anomer containing more than 5% of the α-anomer, i.e., unpurified nicotinamide-β-D-ribofuranoside bromide, chloride, iodide, triflate, perfluorobutanesulfonate, fluorosulfonate or perchlorate or unpurified nicotinamide-2,3,5-O-triacyl-β-D-ribofuranoside bromide, chloride, iodide, triflate, perfluorobutanesulfonate, fluorosulfonate or perchlorate.

[0256] In one embodiment, the salt is provided in dissolved form as produced in the respective synthesis, ie in non-purified form, before use in step (A).

[0257] In summary, the process according to the invention advantageously allows the preparation of nicotinamide-β-D-ribofuranoside salts on various routes, preferably according to routes (P1) to (P5), starting from the pure β-anomer or the β-anomer containing the α-anomer:

[0258] Pathway (P1) includes steps (α), (β), (γ) and (δ):

[0259] (α) cleaving the acyl group of nicotinamide-2,3,5-O-triacyl-β-D-ribofuranoside bromide, chloride, iodide, triflate, perfluorobutylsulfonate, fluorosulfonate or perchlorate containing up to 5% of the α-anomer to obtain nicotinamide-β-D-ribofuranoside bromide, chloride, iodide, triflate, perfluorobutylsulfonate, fluorosulfonate or perchlorate;

[0260] (β) isolating and optionally purifying nicotinamide-β-D-ribofuranoside bromide, chloride, iodide, triflate, perfluorobutanesulfonate, fluorosulfonate or perchlorate;

[0261] (γ) subjecting nicotinamide-β-D-ribofuranoside bromide, chloride, iodide, trifluoromethanesulfonate, perfluorobutylsulfonate, fluorosulfonate or perchlorate to salt metathesis to obtain nicotinamide-β-D-ribofuranoside salt;

[0262] (δ) isolating and optionally purifying the nicotinamide-β-D-ribofuranoside salt.

[0263] Pathway (P2) includes steps (α), (β), (γ) and (δ):

[0264] (α) subjecting nicotinamide-2,3,5-O-triacyl-β-D-ribofuranoside bromide, chloride, iodide, triflate, perfluorobutanesulfonate, fluorosulfonate or perchlorate containing up to 5% of the α-anomer to salt metathesis to obtain nicotinamide-2,3,5-O-triacyl-β-D-ribofuranoside salt;

[0265] (β) isolating and optionally purifying nicotinamide-2,3,5-O-triacyl-β-D-ribofuranoside;

[0266] (γ) cleaving the acyl group of nicotinamide-2,3,5-O-triacyl-β-D-ribofuranoside to obtain nicotinamide-β-D-ribofuranoside;

[0267] (δ) isolating and optionally purifying the nicotinamide-β-D-ribofuranoside salt.

[0268] Pathway (P3) includes steps (α) and (β):

[0269] (α) cleaving the acyl group of nicotinamide-2,3,5-O-triacyl-β-D-ribofuranoside bromide, chloride, iodide, triflate, perfluorobutylsulfonate, fluorosulfonate or perchlorate containing up to 5% of the α-anomer to obtain nicotinamide-β-D-ribofuranoside bromide, chloride, iodide, triflate, perfluorobutylsulfonate, fluorosulfonate or perchlorate, and subjecting the formed nicotinamide-β-D-ribofuranoside bromide, chloride, iodide, triflate, perfluorobutylsulfonate, fluorosulfonate or perchlorate to salt metathesis without prior isolation to obtain nicotinamide-β-D-ribofuranoside salt;

[0270] (β) isolating and optionally purifying the nicotinamide-β-D-ribofuranoside salt.

[0271] Pathway (P4) includes steps (α), (β), (γ) and (δ):

[0272] (α) subjecting nicotinamide-2,3,5-O-triacyl-β-D-ribofuranoside bromide, chloride, iodide, trifluoromethanesulfonate, perfluorobutylsulfonate, fluorosulfonate or perchlorate containing more than 5% of the α-anomer to salt metathesis to obtain nicotinamide-2,3,5-O-triacyl-β-D-ribofuranoside salt;

[0273] (β) isolating and optionally purifying nicotinamide-2,3,5-O-triacyl-β-D-ribofuranoside;

[0274] (γ) cleaving the acyl group of nicotinamide-2,3,5-O-triacyl-β-D-ribofuranoside to obtain nicotinamide-β-D-ribofuranoside;

[0275] (δ) isolating and optionally purifying the nicotinamide-β-D-ribofuranoside salt.

[0276] Pathway (P5) includes steps (α) and (β):

[0277] (α) cleaving the acyl group of nicotinamide-2,3,5-O-triacyl-β-D-ribofuranoside bromide, chloride, iodide, triflate, perfluorobutylsulfonate, fluorosulfonate or perchlorate containing more than 5% of the α-anomer to obtain nicotinamide-β-D-ribofuranoside bromide, chloride, iodide, triflate, perfluorobutylsulfonate, fluorosulfonate or perchlorate, and subjecting the formed nicotinamide-β-D-ribofuranoside bromide, chloride, iodide, triflate, perfluorobutylsulfonate, fluorosulfonate or perchlorate to salt metathesis without prior isolation to obtain nicotinamide-β-D-ribofuranoside salt;

[0278] (β) isolating and optionally purifying the nicotinamide-β-D-ribofuranoside salt.

[0279] The term "without prior separation" used in pathways (P3) and (P5) means that the salt metathesis is carried out in situ.

[0280] Preferably, the salt carrying a pharmaceutically acceptable anion is also formed in situ, ie in the reaction mixture obtained in the cleavage step of the acyl group.

[0281] In one embodiment, various pathways for preparing L-tartrate starting from nicotinamide-2,3,5-O-triacetyl-β-D-ribofuranoside bromide are exemplarily shown in the following scheme:

[0282] Scheme 1: Preparation of nicotinamide starting from nicotinamide-2,3,5-O-triacetyl-β-D-ribofuranoside bromide

[0283] -Pathway P1 to P5 of β-D-ribofuranoside L-tartrate

[0284]

[0285] In another embodiment, various pathways P1 to P5 for preparing L-tartrate starting from nicotinamide-2,3,5-O-triacetyl-β-D-ribofuranoside trifluoromethanesulfonate are exemplarily shown in Scheme 2 (pathways P2 and P3 are not shown):

[0286]

[0287] As described above, in one embodiment, the cleavage of the acyl group in the nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside salt can be carried out under acidic conditions using sulfuric acid, hydrochloric acid or hydrobromic acid or hydroiodic acid. If necessary, the resulting acidic mixture can be neutralized with ammonia or an amine such as triethylamine or tributylamine before isolating the corresponding nicotinamide-β-D-ribofuranoside salt.

[0288] In another embodiment, cleavage of the acyl group in the nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside salt can be performed under basic conditions using ammonia or triethylamine or tributylamine before isolating the corresponding nicotinamide-β-D-ribofuranoside salt.

[0289] Aspect 4: Crystalline nicotinamide-β-D-ribofuranoside hydrogen malate, nicotinamide-β-D-ribofuranoside hydrogen tartrate, nicotinamide-2,3,5-O-triacetyl-β-D-ribofuranoside malate, and nicotinamide-2,3,5-O-triacetyl-β-D-ribofuranoside tartrate

[0290] According to a fourth aspect, the present invention relates to crystalline nicotinamide-β-D-ribofuranoside malate, nicotinamide-β-D-ribofuranoside tartrate, nicotinamide-2,3,5-O-triacetyl-β-D-ribofuranoside malate and nicotinamide-2,3,5-O-triacetyl-β-D-ribofuranoside tartrate.

[0291] In a preferred embodiment, the present invention relates to crystalline nicotinamide-β-D-ribofuranoside hydrogen malate, nicotinamide-β-D-ribofuranoside hydrogen tartrate, nicotinamide-2,3,5-O-triacetyl-β-D-ribofuranoside hydrogen malate and nicotinamide-2,3,5-O-triacetyl-β-D-ribofuranoside hydrogen tartrate.

[0292] In a particularly preferred embodiment, the crystalline nicotinamide-β-D-ribofuranoside hydrogen malate is nicotinamide-β-D-ribofuranoside D-malate hydrogen, characterized by a powder X-ray diffraction pattern having peaks substantially as provided in Table 1 below, ±0.2 degrees 2θ:

[0293] Table 1

[0294]

[0295] In a further particularly preferred embodiment, the crystalline nicotinamide-β-D-ribofuranoside hydrogen malate is nicotinamide-β-D-ribofuranoside L-malate hydrogen, characterized in that the powder X-ray diffraction pattern has peaks substantially as provided in Table 2 below, ±0.2 degrees 2θ:

[0296] Table 2

[0297]

[0298] In another particularly preferred embodiment, the crystalline nicotinamide-β-D-ribofuranoside hydrogen malate is nicotinamide-β-D-ribofuranoside DL-malate hydrogen, characterized by a powder X-ray diffraction pattern having peaks substantially as provided in Table 3 below, ±0.2 degrees 2θ:

[0299] Table 3

[0300]

[0301] In another particularly preferred embodiment, the crystalline nicotinamide-β-D-ribofuranoside bitartrate is nicotinamide-β-D-ribofuranoside D-tartrate monohydrate, characterized by a powder X-ray diffraction pattern having peaks substantially as provided in Table 4 below, ±0.2 degrees 2θ:

[0302] Table 4

[0303]

[0304] In another particularly preferred embodiment, the crystalline nicotinamide-β-D-ribofuranoside bitartrate is nicotinamide-β-L-ribofuranoside L-tartrate, characterized in that the powder X-ray diffraction pattern has peaks substantially as provided in Table 5 below, ±0.2 degrees 2θ:

[0305] Table 5

[0306]

[0307] In another particularly preferred embodiment, the crystalline nicotinamide-β-D-ribofuranoside bitartrate is nicotinamide-β-D-ribofuranoside DL-tartrate, characterized in that the powder X-ray diffraction pattern has peaks substantially as provided in Table 6 below, ±0.2 degrees 2θ:

[0308] Table 6

[0309]

[0310] In another particularly preferred embodiment, the crystalline nicotinamide-2,3,5-triacetyl-β-D-ribofuranoside bitartrate is nicotinamide-2,3,5-triacetyl-β-D-ribofuranoside L-bitartrate, characterized in that the powder X-ray diffraction pattern has peaks substantially as provided in Table 7 below, ±0.2 degrees 2θ:

[0311] Table 7

[0312]

[0313] In another particularly preferred embodiment, the crystalline nicotinamide-2,3,5-triacetyl-β-D-ribofuranoside bitartrate is nicotinamide-2,3,5-triacetyl-β-D-ribofuranoside D-bitartrate, characterized in that the powder X-ray diffraction pattern has peaks substantially as provided in Table 8 below, ±0.2 degrees 2θ:

[0314] Table 8

[0315]

[0316] In another particularly preferred embodiment, the crystalline nicotinamide-β-D-ribofuranoside bitartrate is an anhydrous nicotinamide-β-D-ribofuranoside D-bitartrate, characterized in that the powder X-ray diffraction pattern has peaks substantially as provided in Table 9 below, ±0.2 degrees 2θ:

[0317] Table 9

[0318]

[0319] Therefore, in a particularly preferred embodiment, the present invention relates to a crystalline nicotinamide-β-D-ribofuranoside salt selected from the group consisting of:

[0320] Nicotinamide-β-D-ribofuranoside D-malate, characterized in that Figure 1 A powder X-ray diffraction pattern as defined in;

[0321] Nicotinamide-β-D-ribofuranoside L-malate, characterized in that Figure 2 A powder X-ray diffraction pattern as defined in;

[0322] Nicotinamide-β-D-ribofuranoside DL-malate, characterized in that Figure 3 A powder X-ray diffraction pattern as defined in;

[0323] Nicotinamide-β-D-ribofuranoside D-tartrate hydrogen monohydrate, characterized in that Figure 4 A powder X-ray diffraction pattern as defined in;

[0324] Nicotinamide-β-D-ribofuranoside L-tartrate, characterized in that Figure 5 A powder X-ray diffraction pattern as defined in;

[0325] Nicotinamide-β-D-ribofuranoside DL-tartrate, characterized in that Figure 6 A powder X-ray diffraction pattern as defined in;

[0326] Nicotinamide-2,3,5-O-triacetyl-β-D-ribofuranoside L-tartrate, characterized in that Figure 7 A powder X-ray diffraction pattern as defined in;

[0327] Nicotinamide-2,3,5-O-triacetyl-β-D-ribofuranoside D-tartrate, characterized in that Figure 8 A powder X-ray diffraction pattern as defined in;

[0328] Anhydrous nicotinamide-β-D-ribofuranoside D-tartrate, characterized in that Fig. 9 Powder X-ray diffraction pattern as defined in.

[0329] In another embodiment of the fourth aspect, the invention relates to a nicotinamide-β-D-ribofuranoside salt obtainable by a process as defined in any one of the embodiments of the first or second aspect.

[0330] Fifth aspect: nutritional supplements

[0331] According to a fifth aspect, the present invention relates to a nutritional supplement comprising a nicotinamide-β-D-ribofuranoside salt obtained according to the method defined in the first or second aspect or comprising a nicotinamide-β-D-ribofuranoside salt as defined in the fourth aspect.

[0332] Suitable methods for preparing such nutritional supplements comprising nicotinamide-β-D-ribofuranoside salts are known in the art or can be prepared analogously to such known methods.

[0333] Aspect 6: Pharmaceutical Composition

[0334] According to a sixth aspect, the present invention relates to a pharmaceutical composition comprising a nicotinamide-β-D-ribofuranoside salt obtained according to the method defined in the first or second aspect or comprising a nicotinamide-β-D-ribofuranoside salt defined in the fourth aspect.

[0335] The pharmaceutical composition can be used to prevent or treat diseases related to the nicotinamide riboside kinase pathway or NAD + Diseases or disorders associated with other biosynthetic pathways. These pathways are known in the art.

[0336] Aspect 7: Use of the compound defined in Aspect 4 as a raw material for chemical synthesis

[0337] The crystalline compounds defined in the fourth aspect can be used as starting materials for the preparation of other nicotinamide-β-D-ribofuranoside salts (eg the commercially available chloride) or related compounds due to their purity and ready availability, ie they can be used as starting materials for chemical synthesis.

[0338] According to a seventh aspect, the present invention relates to a method for chemical synthesis, comprising step (A):

[0339] (A) providing a nicotinamide-β-D-ribofuranoside salt obtained by the method defined in the first, second or third aspect, or providing a compound defined in the fourth aspect.

[0340] Eighth aspect: Preparation of nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside trifluoromethanesulfonate or nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside chloride, bromide, iodide, perfluorobutylsulfonate, fluorosulfonate or perchlorate

[0341] The inventors have further modified the method developed by Tanimori disclosed in the third aspect. Hitherto, it was believed that this known method required a significant excess of more than 7.3 equivalents of TMSOTf relative to 1 equivalent of tetra-O-acyl-β-D-ribofuranose to form nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranose trifluoromethanesulfonate that was sufficiently pure for subsequent reactions.

[0342] The inventors of the present invention have surprisingly found that using much less TMSOTf results in a product having a higher purity than that obtained with a significant molar excess of TMSOTf. This is particularly advantageous in economic terms.

[0343] Therefore, in the eighth aspect, the present invention relates to a method for preparing nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside trifluoromethanesulfonate, the method comprising step (A):

[0344] (A) Nicotinamide is reacted with tetra-O-acyl-β-D-ribofuranose in the presence of 0.9 to 1.5 molar equivalents of TMSOTf relative to 1 mole of tetra-O-acyl-β-D-ribofuranose.

[0345] It is preferred to use 1.0 to 1.5 molar equivalents of TMSOTf, more preferably 1.0 to 1.3 molar equivalents, still more preferably 1.0 to 1.2 molar equivalents.

[0346] Preference is given to using acetonitrile as solvent.

[0347] Preferably, the reaction is carried out at a temperature ranging from 10 to 40°C, more preferably from 20 to 30°C.

[0348] After removing the solvent, nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside trifluoromethanesulfonate can be obtained in the form of an amorphous foam.

[0349] The acyl group can then be cleaved according to known methods to give nicotinamide-β-D-ribofuranoside triflate.

[0350] Both the acylated product and the deacylated product can be used in the corresponding methods according to the present invention defined in the first, second and third aspects.

[0351] In one embodiment, the nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside triflate is not isolated prior to salt metathesis or deacylation.

[0352] The iodide can be prepared in a similar manner. Therefore, in this aspect the present invention relates to a method for preparing nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside iodide, the method comprising the steps (A):

[0353] (A) Nicotinamide is reacted with tetra-O-acyl-β-D-ribofuranose in the presence of 0.9 to 1.5 molar equivalents of TMSI relative to 1 mole of tetra-O-acyl-β-D-ribofuranose.

[0354] Preferably, the reaction is carried out at a temperature ranging from 10 to 50°C, more preferably from 20 to 40°C.

[0355] This reaction can also be extended to the preparation of bromide, chloride, perfluorobutylsulfonate, fluorosulfonate and perchlorate. Therefore, in one embodiment, this aspect also relates to a method for preparing nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside bromide, chloride, perfluorobutylsulfonate, fluorosulfonate or perchlorate, the method comprising step (A):

[0356] (A) Nicotinamide is reacted with tetra-O-acyl-β-D-ribofuranose in the presence of 0.9 to 1.5 molar equivalents of TMSBr, TMSC, TMSOSO2C4F9, TMSOSO2F or TMSOClO3 relative to 1 mole of tetra-O-acyl-β-D-ribofuranose.

[0357] The synthesis of iodides is particularly preferred due to the high yield and purity of the products formed as well as the economic advantages.

[0358] Ninth aspect: Nicotinamide-β-D-furanosyl iodide, perfluorobutyl sulfonate, fluorosulfonate, perchlorate, Nicotinamide-2,3,5-tri-O-acyl-β-D-furanosyl iodide, perfluorobutyl sulfonate, fluorosulfonate, perchlorate

[0359] According to a ninth aspect, the present invention relates to

[0360] Nicotinamide-β-D-ribofuranoside iodide, perfluorobutylsulfonate, fluorosulfonate or perchlorate of the formula

[0361] I - 、n-F9C4SO3 - 、FSO3 - 、ClO4 - ;

[0362] and nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside iodide, perfluorobutylsulfonate, fluorosulfonate or perchlorate of the formula

[0363] I - 、n-C4F9SO3 - 、FSO3 - , ClO4 -

[0364] wherein R is acyl, independently selected from alkylcarbonyl, arylcarbonyl and heteroarylcarbonyl, preferably selected from C 1-10 alkylcarbonyl and benzoyl, and more preferably acetyl, and wherein R is optionally substituted independently by one or more substituents selected from the group consisting of: C 1-6 Alkyl, C 1-6 Alkoxy, C 1-6 Thioalkyl, halogen, nitro, cyano, NH(C 1-6 Alkyl), N(C 1-6 alkyl)2 and SO2N(C 1-6 alkyl)2; preferably wherein R is acetyl.

[0365] In another aspect of the invention, in steps (X) and (Y) as defined in the first and second aspects, the nicotinamide used in the synthesis according to the invention is used in precursor form, ie in the form of a nicotinic acid ester.

[0366] In one embodiment, the ester moiety is selected from C 1-10 In another embodiment, the ester moiety is a phenoxy group, which may be branched or unbranched or cyclic. In another embodiment, the ester moiety is a benzyloxy group, which may be substituted. As used herein, the term "optionally substituted" refers to a C 1-6 Alkyl, C 1-6 Alkoxy, C 1-6 Thioalkyl, halogen, nitro, cyano, NH(C 1-6 Alkyl), N(C 1-6alkyl)2 and SO2N(C 1-6 Alkyl)2.

[0367] Subsequently, the respective compound having a nicotinate moiety can be subjected to salt metathesis as described above.

[0368] Finally, the nicotinic acid ester portion of each compound is transferred to the nicotinamide portion using ammonia.

[0369] In another aspect, the present invention relates to a method for preparing a second nicotinamide-β-D-ribofuranoside salt from a first nicotinamide-β-D-ribofuranoside salt, or preparing a second nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside salt from a first nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside salt, comprising steps (A1) and (A2):

[0370] (A1) NH3 or NR 1 H2 or NR 1 R 2 H or NR 1 R 2 R 3 or [NR 1 R 2 R 3 R 4 ]OH reacts with acid to obtain ammonium salt, where R 1 , R 2 , R 3 and R 4 Independently selected from C 1-12 Alkyl and aryl groups are optionally substituted.

[0371] (A2) reacting the first nicotinamide-β-D-ribofuranoside salt or the first nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside salt with the ammonium salt from step (A1) to perform salt metathesis including counterion exchange to obtain a second nicotinamide-β-D-ribofuranoside salt or a second nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside salt.

[0372] In a preferred embodiment, NR is used in step (A1). 1 R 2 R 3 or [NR 1 R 2 R 3 R 4 ]OH.

[0373] The acetyl residue used in the nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside salt is as defined above.

[0374] Preferably, step (A2) is carried out in a solvent comprising an alcohol, wherein the alcohol is selected from the group consisting of methanol, ethanol, propanol or butanol or a mixture of two or more thereof, optionally comprising water; or the solvent is selected from the group consisting of methanol, ethanol, propanol or butanol or a mixture of two or more thereof, optionally comprising water.

[0375] In another aspect, the present invention relates to a + or NR 1 H3 + or NR 1 R 2 H2 + or NR 1 R 2 R 3 H + or [NR 1 R 2 R 3 R 4 ] + Use of an ammonium salt of 1 , R 2 , R 3 and R 4 Independently selected from C 1-12 Alkyl and aryl groups are optionally substituted.

[0376] Preferably, the nicotinamide-β-D-ribofuranoside salt or the nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside salt is subjected to salt metathesis.

[0377] The acetyl residue used in the nicotinamide-2,3,5-tri-O-acyl-β-D-ribofuranoside salt is as defined above.

[0378] Preferably, the salt metathesis reaction is carried out in a solvent comprising an alcohol, wherein the alcohol is selected from the group consisting of methanol, ethanol, propanol or butanol or a mixture of two or more thereof, optionally wherein the solvent or alcohol comprises water; or the solvent is selected from the group consisting of methanol, ethanol, propanol or butanol or a mixture of two or more thereof, optionally comprising water.

[0379] The following examples further illustrate the present invention.

[0380] Example

[0381] Example 1: Preparation of Nicotinamide-2,3,5-Tri-O-acetyl-β-D-ribofuranoside Bromide Used as Starting Salt in Step (A) of the Method According to the Second or Third Aspect

[0382] 274 g of β-D-ribofuranose 1,2,3,5-tetraacetate are dissolved in 274 ml of acetonitrile. 180 ml of hydrogen bromide in glacial acetic acid (concentration 33%) are added to the stirred solution, while maintaining the temperature between 0°C and 5°C. Stirring is continued for 15 minutes. 41 g of nicotinamide are added, while stirring for another 15 minutes. A hot (70°C) solution of 96 g of nicotinamide in 700 ml of acetonitrile is then added, and the mixture is then cooled to about 0°C to 5°C. Stirring is continued for 15 h, and the suspension formed is subsequently filtered. The filtrate is distilled. The oily residue obtained is diluted with acetone to crystallize the title product. The title product is filtered and dried to give 167 g (43% yield) of an almost colorless product; Mp: 133-134°C.

[0383] 1 H-NMR (400MHz, DMSO-d6): 2.09(s,6H),2.13(s,3H)4.45(m,2H,H5'),4.69(m,1H,H4'),5.43(t,1H,H3'),5.62(dd,1H,H2' ),6.69(d,1H,H1'),8.23(s,1H,NH),8.41(dd,1H,H5),8.74(s,1H,NH),9.13(d,1H,H4),9.28(d,1H,H6),9.49(s,1H,H2);

[0384] 13 C-NMR (100MHz, DMSO-d6): 20.3, 20.4, 20.5, 62.1 (C5'), 68.7 (C3'), 75.3 (C2'), 81.8 (C4'), 97.2 (C 1'),128.1(C5),133.9(C3),141.2(C2),143.1(C6),145.5(C4),162.7(CONH2),169.2,169.4,170.1

[0385] Example 2: Preparation of Nicotinamide-β-D-ribofuranoside Bromide Used as Starting Salt in Step (A) of the Method According to the First Aspect

[0386] 167 g of the product obtained in Example 1 were dissolved in 870 ml of methanol. Then 135 ml of hydrogen bromide (concentration 33%) in acetic acid was added to the stirred solution while maintaining the temperature at 5°C to 10°C. The resulting mixture was stirred at 20°C for two days and the product began to crystallize. The formed crystals were filtered off, washed with isopropanol and dried. The title compound was obtained in a yield of 77 g (63%) as a light yellow crystalline powder; Mp: 118-119°C.

[0387] 1H-NMR(400MHz,D2O): 3.83(dd,1H,H5'),3.98(dd,1H,H5'),4.29(t,1H,H3'),4.39-4.48(m,2H, H4',H2'),6.18(d,1H,H1'),8.22(t,1H,H5),8.91(d,1H,H4),9.20(d,1H,H6),9.52(s,1H,H2);

[0388] 13 C-NMR(100MHz,D2O): 60.0(C5'),69.5(C3'),77.2(C2'),87.5(C4'),99.7(C1 '),128.3(C5),133.7(C3),140.2(C2),142.5(C6),145.5(C4),165.6(CONH2).

[0389] Example 3: Preparation of Nicotinamide-β-D-ribofuranoside L-tartrate from Nicotinamide-β-D-ribofuranoside Bromide Using Various L-tartrate Ammonium Salts for Salt Metathesis

[0390] Example 3a: Use of TEA·L-tartrate

[0391] 3.90 g L-tartaric acid (26.0 mMol) were dissolved in 10 ml methanol with stirring. The colorless solution was cooled in an ice bath and 3.64 ml triethylamine (26.1 mMol) were added. The pH of the slightly yellow solution was about 4–4.5. In this way, 15 ml of a 1.73 molar TEA·L-tartrate solution were prepared.

[0392] At room temperature, 5.8 g of nicotinamide-β-D-ribofuranoside bromide (NR·Br) was dissolved in 3.5 ml of water under stirring. 10 ml of methanol was added. 10 ml of the L-triethylammonium hydrogen tartrate solution prepared above was added to the colorless transparent solution. A white product began to precipitate.

[0393] The suspension is stirred at room temperature for a further hour. The product is filtered, washed with methanol and dried in vacuo at 35°C. 6.62 g (95%) of a white crystalline powder are obtained; mp: 129-130°C; IC: residual bromide 0.20%. If desired, the solid can be recrystallized from aqueous methanol.

[0394] 1H-NMR (400MHz, D2O): 3.82 (dd, 1H, H5'), 3.97 (dd, 1H, H5'), 4.28 (t, 1H, H3'), 4.38-4.45 (m, 2H, H4', H2'), 4.41 (s, 2H, 2x CHOH, H-tartrate), 6.17 (d, 1H, H1'), 8.20 (t, 1H, H5), 8.90 (d, 1H, H4), 9.19 (d, 1H, H6), 9.52 (s, 1H, H2). Impurities: <1mol% nicotinamide; 1.2mol% TEA salt: 1.19 (t, 9H), 3.11 (q, 6H). Solvent: 7.3mol% methanol: 3.25 (s, 3H).

[0395] 13 C-NMR (100MHz, D2O): 60.2 (C5'), 69.7 (C3'), 72.8 (2x CHOH, H-tartaric acid), 77.4 (C2'), 87.6 (C4'), 99.9 (C1'), 128.4 (C5), 133.9 (C3), 140.4 (C2), 142.6 (C6), 145.6 (C4), 165.8 (CONH2), 176.3 (2x COO, H-tartaric acid). Impurities: 8.2, 46.6 (TEA). Solvent: 48.9 (methanol).

[0396] XRD: Crystal( Figure 5 )

[0397] Example 3b: Use of TBA·L-tartrate

[0398] 3.90 g of L-tartaric acid (26.0 mMol) were dissolved in 10 ml of methanol with stirring. The colorless solution was cooled in an ice bath and 6.3 ml of tributylamine (26.0 mMol) were added. The pH of the slightly yellow solution was about 4. In this way, 17.5 ml of a 1.53 molar L-tributylammonium hydrogen tartrate solution were prepared.

[0399] At room temperature, 5.80 g of nicotinamide-β-D-ribofuranoside bromide was dissolved in 3.5 ml of water under stirring. 10 ml of methanol was added. 11.1 ml of the L-tributylammonium hydrogen tartrate solution prepared above was added to the colorless transparent solution. The white product immediately began to crystallize.

[0400] The suspension was stirred at room temperature for another hour. The product was filtered, washed with methanol and dried in vacuo at 35° C. 6.37 g (91%) of a white crystalline powder were obtained; mp: 128° C.; IC: residual bromide 0.62%.

[0401] Impurities (NMR): <1 mol% nicotinamide, 2.7 mol% TBA salt: 0.84 (t, 9H), 1.28 (m, 6H), 1.58 (m, 6H), 3.04 (q, 6H); solvent: 3.7 mol% methanol: 3, 25 (s, 3H).

[0402] Example 3c: Using L-tetrabutylammonium hydrogen tartrate

[0403] 3.90 g of L-tartaric acid (26.0 mMol) were dissolved in 10 ml of methanol with stirring. The colorless solution was cooled in an ice bath and 17.0 ml of a 40% aqueous solution of tetrabutylammonium hydroxide (26.0 mMol) were added. The pH of the slightly yellow solution was about 4. In this way, 29 ml of a 0.9 molar solution of L-tetrabutylammonium hydrogen tartrate was prepared.

[0404] At room temperature, 5.80 g of nicotinamide-β-D-ribofuranoside bromide was dissolved in 3.5 ml of water under stirring. 10 ml of methanol was added. 19.3 ml of the L-tetrabutylammonium hydrogen tartrate solution prepared above was added to the colorless transparent solution. A white product began to crystallize.

[0405] The suspension was stirred at room temperature for another hour. The product was filtered, washed with methanol and dried in vacuo at 35° C. 5.60 g (80%) of a white crystalline powder were obtained; mp: 129-130° C.; IC: residual bromide 0.13%.

[0406] Impurities (NMR): <1 mol% nicotinamide; 0.35 mol% TBA salt: 0.36 (t, 9H), 1,27 (m, 6H), 1,56 (m, 6H), 3.11 (q, 6H); solvent: 2.4 mol% methanol: 3.26 (s, 3H).

[0407] Example 4: Similar to Example 3a, the following crystalline nicotinamide-β-D-furanosyl salt was prepared:

[0408] Table 1

[0409]

[0410] Example 5: Preparation of Nicotinamide-β-D-ribofuranoside L-Malate from Nicotinamide-β-D-ribofuranoside Bromide Using Various L-Ammonium Hydrogen Malate Salts for Salt Metathesis

[0411] Example 5a: Using TEA·L-malate

[0412] 5.8 g of nicotinamide-β-D-ribofuranoside bromide are suspended in 10 ml of methanol under stirring. 10 ml of 1.73 molar L-triethylammonium hydrogenmalate solution are added. The suspension is heated until the solid is completely dissolved. After cooling, a white solid precipitates. The suspension is stirred for 30 minutes and then filtered. The residue is washed with methanol and dried in vacuo at 35°C. 4.15 g (62%) of a white crystalline powder are obtained. Mp: 116.5-117°C. IC: Residual bromide 0.10%. If necessary, the product can be recrystallized from methanol.

[0413] 1 H-NMR (400MHz, D2O): 2.53 (dd, 1H, CH2, H-malic acid), 2.72 (dd, 1H, CH2, H-malic acid), 3.81 (dd, 1H, H5'), 3.97 (dd, 1H, H5'), 4.28 (t, 1H, H3'), 4.29 (dd, 1H, CHOH, H-malic acid), 4.38-4.45 (m, 2H, H4', H2'), 6.17 (d, 1H, H1'), 8.20 (t, 1H, H5), 8.90 (d, 1H, H4), 9.19 (d, 1H, H6), 9.52 (s, 1H, H2). Impurities: <1mol% nicotinamide; 0.7mol% TEA salt: 1.19 (t, 9H), 3.11 (q, 6H). Solvent: 6.3 mol% Methanol: 3.25 (s, 3H).

[0414] 13 C-NMR (100 MHz, D2O): 40.0 (CH2, H-malic acid), 60.2 (C5'), 68.5 (CHOH, H-malic acid), 69.7 (C3'), 77.4 (C2'), 87.7 (C4'), 99.9 (C1'), 128.4 (C5), 133.9 (C3), 140.4 (C2), 142.6 (C6), 145.6 (C4), 165.7 (CONH2), 176.3 (COO, H-malic acid), 179.0 (COO, H-malic acid). Solvent: 48.9 (methanol).

[0415] XRD: Crystal( Figure 2 )

[0416] Example 5b: Using TBA·L-malate

[0417] 3.50 g of L-malic acid (26.0 mMol) were dissolved in 10 ml of methanol with stirring. The colorless solution was cooled in an ice bath and 6.3 ml of tributylamine (26.0 mMol) were added. The pH of the slightly yellow solution was about 5. In this way, 17.5 ml of a 1.53 molar solution of L-tributylammonium hydrogenmalate were prepared.

[0418] 5.80 g of nicotinamide-β-D-ribofuranoside bromide were suspended in 17.5 ml of methanol under stirring. 11.1 ml of the L-tributylammonium hydrogenmalate solution prepared above were added. The suspension was heated until the solid was completely dissolved. After cooling, a white solid crystallized. The suspension was stirred for 30 minutes and then filtered. The residue was washed with methanol and dried in vacuo at 35°C. 4.89 g (73%) of a white crystalline powder were obtained; mp: 115.5°C; IC: residual bromide 0.64%.

[0419] Impurities: <1 mol% nicotinamide; 0.2 mol% TBA salt; 2 mol% methanol.

[0420] Example 6: Similar to Example 5a, the following crystalline nicotinamide-β-D-furanosyl salt was prepared:

[0421] Table 2

[0422]

[0423] Example 6d: Compound 6c was recrystallized as a monohydrate

[0424] 2.0 g of nicotinamide-β-D-furanosyl D-tartrate prepared in Example 6c were dissolved in 9 ml of water. 70 ml of methanol were added to the colorless solution with stirring. White crystals precipitated after about one minute. The suspension formed was filtered after one hour. The residue was washed with methanol and dried in vacuo at 35°C. 1.54 g (77%) of the monohydrate as a white crystalline powder were obtained. Water content: 4.24% (determined according to K. Fischer); Mp.: 115-116°C; IC: residual bromide: <0.01%.

[0425] XRD: Crystal( Figure 4 )

[0426] Example 7: Preparation of Nicotinamide-β-D-Ribofuranosyl Meso-tartrate

[0427] 0.57 g of nicotinamide-β-D-ribofuranoside bromide was suspended in 1 ml of methanol under stirring. 1 ml of 1.69 molar meso-triethylammonium hydrogen tartrate solution was added. The suspension was heated to boiling point and then cooled. The emulsion formed was dripped into 20 ml of ethanol. The suspension formed was filtered and the residue was dried under vacuum at room temperature. 0.44 g (62%) of flaky hygroscopic powder was obtained.

[0428] 1 H-NMR (400 MHz, D2O): 3.82 (dd, 1H, H5'), 3.97 (dd, 1H, H5'), 4.28 (t, 1H, H3'), 4.38-4.46 (m, 2H, H4', H2'), 4.35 (s, 1.5H, 2x CHOH, meso-H-tartaric acid), 6.17 (d, 1H, H1'), 8.21 (t, 1H, H5), 8.91 (d, 1H, H4), 9.20 (d, 1H, H6), 9.53 (s, 1H, H2). Impurities: 5mol% nicotinamide: 7.65 (m, 1H), 8.33 (m, 1H), 8.68 (d, 1H), 8.90 (s, 1H); 10.2mol% TEA salt: 1.20 (t, 9H), 3.12 (q, 6H). Solvent: 16mol% methanol: 3.25 (s, 3H); 40mol% ethanol: 1.09 (t, 3H), 3.56 (q, 2H).

[0429] 13 C-NMR (100MHz, D2O): 60.2 (C5'), 69.7 (C3'), 73.7 (2x CHOH, meso-H-tartaric acid), 77.4 (C2'), 87.6 (C4'), 99.9 (C1'), 128.4 (C5), 133.9 (C3), 140.4 (C2), 142.6 (C6), 145.6 (C4), 165.8 (CONH2), 175.7 (2x COO, H-tartaric acid). Impurities: 125.0, 138.6, 146.0, 149.8 (nicotinamide); 8.2, 46.6 (TEA). Solvents: 48.9 (methanol); 16.8, 57.4 (ethanol).

[0430] Example 8: Preparation of Nicotinamide-β-D-furanosyl D-glucuronide

[0431] 5.10 g of glucuronic acid are suspended in 15 ml of methanol with stirring. The colorless suspension is cooled in an ice bath and 3.60 ml of triethylamine are added. 19.5 ml of a 1.35 molar TEA·D-glucuronide solution are prepared.

[0432] At room temperature, 5.0 g of nicotinamide-β-D-ribofuranoside bromide was dissolved in 3.0 ml of water under stirring. 10 ml of methanol was added. 11.1 ml of the triethylammonium D-glucuronic acid solution prepared above was added. The clear light yellow solution was slowly dripped into 455 ml of n-butanol to produce a white suspension.

[0433] The suspension was stirred for a further 5 hours at room temperature. The product was filtered, washed with isopropanol and dried in vacuo at 35°C. 6.64 g of the dried crude product was dissolved in 6.6 ml of water and diluted with 33 ml of methanol. The pale yellow solution was dropped into 550 ml of butanol to produce a white suspension. The suspension was filtered, the residue was washed with isopropanol and dried at 35°C. Mp: 66-76°C; residual bromide 1.43% (IC).

[0434] 1 H-NMR (400 MHz, D2O): NR: 3.82 (dd, 1H, H5'), 3.97 (dd, 1H, H5'), 4.28 (t, 1H, H3'), 4.38-4.45 (m, 2H, H4', H2'), 6.17 (d, 1H, H1'), 8.21 (t, 1H, H5), 8.91 (d, 1H, H4), 9.20 (d, 1H, H6), 9.53 (s, 1H, H2); GlcUA (anomeric mixture): 3.19 (m), 3.42 (m), 3.50 (m), 3.63 (m), 4.00 (t), 4.55 (d, β-anomer), 5.14 (d, α-anomer). Impurities: 2 mol% Nicotinamide: 0.9 mol% TEA salt: 1.19 (t, 9H), 3.11 (q, 6H). Solvent: 23 mol% methanol: 3.26 (s, 3H); 5.7 mol% butanol: 0.80 (t, 1H, H4), 1.25 (m, 2H, H3), 1.43 (m, 2H, H2).

[0435] 13 C-NMR (100 MHz, D2O): NR: 60.2 (C5'), 69.7 (C3'), 77.4 (C2'), 87.6 (C4'), 99.9 (C1'), 128.4 (C5), 133.9 (C3), 140.4 (C2), 142.6 (C6), 145.6 (C4), 165.8 (CONH2); GlcUA: 71.3, 71.7, 71.8, 72.0, 72.5, 74.0, 75.5, 76.1, 92.1, 95.9, 175.7, 176.7. Solvent: 48.9 (methanol); 13.1, 18.4, 33.4, 61.5 (butanol).

[0436] Example 9: Nicotinamide-β-D-ribofuranoside L-ascorbate

[0437] The crude product was prepared similarly to Example 8, but ethanol was used for precipitation. 3.11 g of the crude product was dissolved in 1.9 ml of water. The orange clear solution was filtered and diluted with 16 ml of methanol. The solution was dropped into 238 ml of ethanol to produce an orange suspension. The product was isolated by filtration and dried at 35° C. 1.13 g of a light yellow powder was obtained (yield 36.3%). IC: residual bromide 0.38%.

[0438] 1 H-NMR (400MHz, D2O): 3.82 (dd, 1H, H5'), 3.97 (dd, 1H, H5'), 4.28 (t, 1H, H3'), 4.38-4.45 (m, 2H, H4', H2'), 6.17 (d, 1H, H1'), 8.20 (t, 1H, H5), 8.90 (d, 1H, H4), 9.19 (d, 1H, H6), 9.52 (s, 1H, H2); Ascorbic acid: 3.64 (m, 2H), 3.92 (m, 1H), 4.43 (m, 1H). Impurities: 16 mol% Nicotinamide: 7.49 (t, 1H), 8.13 (d, 1H), 8.60 (d, 1H), 8.82 (s, 1H); No TEA salt. Solvent: 1.3 mol% methanol: 3.25 (s, 3H); 46 mol% ethanol: 1.08 (t, 3H), 3.55 (q, 2H).

[0439] 13 C-NMR (100MHz, D2O): 60.2 (C5'), 69.7 (C3'), 77.4 (C2'), 87.7 (C4'), 99.9 (C1'), 128.4 (C5), 133.9 (C3), 140.4 (C2), 142.6 (C6), 145.6 (C4), 165.8 (CONH2); Ascorbic acid: 62.5, 69.5, 78.2, 113.3, 174.6, 177.2. Impurities: Nicotinamide: 124.2, 129.3, 136.5, 147.6, 151.7. Solvent: 16.8, 57.4 (ethanol).

[0440] Example 10: Nicotinamide-β-D-ribofuranoside citrate

[0441] 5.52 g of citric acid monohydrate were dissolved in 55 ml of DMSO with stirring. The colorless solution was cooled in an ice bath and 12 ml of triethylamine were added. 73 ml of a 0.36 molar TEA·citrate solution was prepared.

[0442] 9.0 g of nicotinamide-β-D-ribofuranoside bromide was suspended in 18 ml of DMSO. 73 ml of the solution produced above was added and heated to 55° C. The light brown solution was added to 1125 ml of isopropanol to produce a white suspension. The solid was separated by filtration and dried at 35° C. 6.32 g (74%) of powder was obtained.

[0443] 3.22 g of the crude product was dissolved in a mixture of 16 ml of methanol and 2 ml of water. The solution was dropped into 220 ml of isopropanol to produce a white suspension. The solid was separated by filtration, washed with isopropanol and dried in vacuo at 35°C. 2.67 g of a white powder (82.9%) were obtained. IC: Residual bromide 0.19%.

[0444] 1 H-NMR (400MHz, D2O): 2.61 (m, 4H, CH2, citric acid), 3.82 (dd, 1H, H5'), 3.97 (dd, 1H, H5'), 4.28 (t, 1H, H3'), 4.38-4.46 (m, 2H, H4', H2'), 6.17 (d, 1H, H1'), 8.21 (t, 1H, H5), 8.90 (d, 1H, H4), 9.20 (d, 1H, H6), 9.52 (s, 1H, H2). Impurities: 6mol% nicotinamide: 7.50 (dd, 1H), 8.15 (m, 1H), 8.61 (d, 1H), 8.82 (s, 1H); 1.5mol% TEA salt: 1.19 (t, 9H), 3.11 (q, 6H). Solvent: 31 mol% methanol: 3.26 (s, 3H); 18 mol% isopropanol: 1.08 (d, 6H), 3.92 (m, 1H).

[0445] 13 C-NMR (100MHz, D2O): 44.6 (CH2, citric acid), 60.2 (C5'), 69.7 (C3'), 77.4 (C2'), 87.7 (C4'), 99.9 (C1'), 128.4 (C5), 133.9 (C3), 140.4 (C2), 142.6 (C6), 145.6 (C4), 165.7 (CONH2), 176.9 (2x COO, citric acid), 180.0 (COO, citric acid). Impurities: Nicotinamide: 124.3, 129.3, 136.7, 147.5, 151.6; TEA salt: 8.2, 46.6. Solvent: 48.9 (methanol); 23.7, 64.2 (isopropanol).

[0446] Example 11: Preparation of Nicotinamide-β-D-riboside-2,3,5-triacetic acid L-tartrate

[0447] Example 11a: Metathesis via salt of nicotinamide-β-D-riboside-2,3,5-triacetic acid bromide

[0448] 3.90 g of L-tartaric acid was dissolved in 10 ml of methanol under stirring. The solution was cooled to 0-5°C and 3.64 ml of triethylamine was added. The pH value was 4.1. 15 ml of 1.73 mol L-triethylammonium hydrogen tartrate solution was obtained.

[0449] Suspend 8.0 g of nicotinamide-2,3,5-tri-O-acetyl-β-D-riboside bromide in 10 ml of methanol under stirring. Add 10 ml of the L-tetraethylammonium hydrogen tartrate solution generated above. A white crystalline powder begins to precipitate slowly. The residue obtained after filtration is dried under vacuum at 35°C. 6.00 g (65.2%) of a white crystalline powder is obtained. Mp. 128°C; IC: Residual bromide < 0.1%.

[0450] 1 H-NMR (400MHz, D2O): 2.08, 2.12, 2.15 (3x s, 3x 3H, COCH3), 4.43 (s, 2H, 2xCHOH, H-tartaric acid), 4.52 (m, 2H, H5'), 4.88 (m, 1H, H4'), 5.44 (t, 1H, H3'), 5.55 (dd, 1H, H2'), 6.58 (d, 1H, H1'), 8.27 (t, 1H, H5), 8.99 (d, 1H, H4), 9.20 (d, 1H, H6), 9.43 (s, 1H, H2). Impurities: <0.1mol% nicotinamide; 0.6mol% TEA salt: 1.21 (t, 9H), 3.13 (q, 6H). Solvent: 2 mol% methanol: 3.27 (s, 3H).

[0451] 13 C-NMR (100 MHz, D2O): 19.8, 19.9, 20.2 (3x COCH3), 62.6 (C5'), 69.4 (C3'), 72.8 (2x CHOH, H-tartaric acid), 76.3 (C2'), 82.6 (C4'), 97.3 (C1'), 128.6 (C5), 134.2 (C3), 140.4 (C2), 143.1 (C6), 146.2 (C4), 165.5 (CONH2), 172.3, 172.4, 173.3 (3xCO), 176.3 (2x COO, H-tartaric acid).

[0452] XRD: Crystal( Figure 7 ).

[0453] Example 11b: Ion exchange by using an ion exchanger (for comparison)

[0454] 145 g of Ambersep 900 in OH form were suspended in 110 ml of water. Subsequently, 21 g of L-tartaric acid were added with stirring. The ion exchanger loaded with L-tartrate was separated by filtration and washed three times with water.

[0455] 10.0 g of nicotinamide-2,3,5-tri-O-acetyl-β-D-riboside bromide was dissolved in 70 ml of water under stirring. 22 g of loaded ion exchanger was added and stirred for 16 minutes. The ion exchanger was separated by filtration and washed twice with water. The filtrate was subjected to 22 g of loaded ion exchanger again and washed and filtered, and the filtrate was collected. Repeated twice. The filtrate was concentrated. 14.08 g of colorless oil was obtained. The oil was subjected to methanol aqueous solution to obtain a white suspension. 9.09 g of white powder was obtained after filtration and drying.

[0456] 5.05 g of the amorphous product was dissolved in 25 ml of methanol and crystallization started after a few minutes. The crystals were separated by filtration and dried in vacuo at 35° C. 3.92 g, mp. 130° C. XRD was identical to that of the product obtained in Example 11a.

[0457] Example 12: Preparation of Nicotinamide-2,3,5-Tri-O-acetyl-β-D-ribofuranoside Trifluoromethanesulfonate Example 12a: According to the present invention

[0458] At room temperature, 11.55 g (0.094 mole) of nicotinamide and 29.7 g (0.093 mole) of β-D-ribofuranose 1,2,3,5-tetraacetate were dissolved in 750 ml of a mixture of 4% zeolite and 1% d-d-pyrido[1,2,3,5-tetraacetate under stirring. 18.2 ml (0.097 mol) of trimethylsilyl trifluoromethanesulfonate were added over 20 minutes. The yellow solution was stirred for 20 minutes. Subsequently, the solvent was removed in vacuo at 35°C. The foam formed was dissolved in 300 ml of dichloromethane and 4.5 g of activated carbon were added. The suspension was filtered. The filtrate was concentrated. 49.5 g (100%) of yellow foam were obtained.

[0459] 1 H-NMR (400 MHz, D2O): 2.02, 2.06, 2.09 (3x s, 3x 3H, COCH3), 4.45 (m, 2H, H5'), 4.82 (m, 1H, H4'), 5.38 (t, 1H, H3'), 5.49 (dd, 1H, H2'), 6.51 (d, 1H, H1'), 8.22 (t, 1H, H5), 8.92 (d, 1H, H4), 9.13 (d, 1H, H6), 9.37 (s, 1H, H2). Impurities: 3 mol% α-anomer, 4 mol% nicotinamide.

[0460] 13 C-NMR (100MHz, D2O): 19.8, 19.9, 20.2 (3x COCH3),62.6(C5'),69.4(C3'),76.4(C2'),82.7(C4'),97.3(C1');114.9+118.1+121.2+124.4(q,CF 3);128.7(C5),134.2(C3),140.4(C2),143.1(C6),146.2(C4),165.5(CONH2),172.3,172.4,173.3(3x CO).

[0461] Example 12b: For comparison

[0462] The process was carried out as described by Tanimori using a high excess of trimethylsilyl triflate, with the product isolated as described in Example 12a. The foam obtained contained a mixture of approximately β-anomer:α-anomer:nicotinamide = 2:1:1.

[0463] Example 13: Preparation of Nicotinamide-β-D-riboside-2,3,5-triacetic acid L-tartrate from Nicotinamide-β-D-riboside-2,3,5-triacetic acid trifluoromethanesulfonate prepared according to Example 12

[0464] 5.00 g of nicotinamide-2,3,5-tri-O-acetyl-β-D-ribofuranoside trifluoromethanesulfonate of Example 12 was dissolved in 50 ml of ethanol. 1.42 g of L-tartaric acid was added. Subsequently, 1.31 ml of triethylamine was added. The resulting emulsion was heated for a short time to promote crystallization and then cooled. The precipitate formed was separated by filtration and dried in vacuo at 30° C. 5.07 g (101.4%) of a white crystalline powder (mp 127° C.) was obtained.

[0465] 1H-NMR (400MHz, D2O): 2.08, 2.12, 2.16 (3x s, 3x 3H, COCH3), 4.43 (s, 2H, 2xCHOH, H-tartaric acid), 4.52 (m, 2H, H5'), 4.88 (m, 1H, H4'), 5.44 (t, 1H, H3'), 5.56 (dd, 1H, H2'), 6.58 (d, 1H, H1'), 8.28 (t, 1H, H5), 8.99 (d, 1H, H4), 9.20 (d, 1H, H6), 9.43 (s, 1H, H2). Impurities: <1mol% nicotinamide; 0.35mol% TEA salt: 1.21 (t, 9H), 3.13 (q, 6H). Solvent: 2 mol% ethanol: 3.57 (q, 2H), 1.10 (t, 3H).

[0466] 13 C-NMR (100 MHz, D2O): 19.8, 19.9, 20.2 (3x COCH3), 62.6 (C5'), 69.4 (C3'), 72.8 (2x CHOH, H-tartaric acid), 76.3 (C2'), 82.6 (C4'), 97.3 (C1'), 128.6 (C5), 134.2 (C3), 140.4 (C2), 143.1 (C6), 146.3 (C4), 165.5 (CONH2), 172.3, 172.4, 173.3 (3x CO), 176.3 (2x COO, H-tartaric acid).

[0467] Example 14: Preparation of Nicotinamide-β-D-riboside-2,3,5-triacetic acid D-tartrate from Nicotinamide-β-D-riboside-2,3,5-triacetic acid bromide

[0468] Preparation of crystalline nicotinamide-2,3,5-O-triacetyl-β-D-riboside D-tartrate according to Example 11a

[0469] For comparison, the product was prepared according to the method of Example 11b. The amorphous product subjected to crystallization was identical to the product obtained in Example 11a.

[0470] XRD shows Figure 8 .

[0471] Example 15: Deacylation of Nicotinamide-β-D-riboside-2,3,5-triacetic acid L-tartrate (from Example 11) illustrating Pathway 2

[0472] Example 15a: Deacylation with sulfuric acid and neutralization with triethylamine

[0473] Preparation of dilute sulfuric acid in methanol: 27 g of methanol was cooled to 0° C. 3.00 g of sulfuric acid was added under stirring to obtain 10% methanolic sulfuric acid.

[0474] Deacylation of Nicotinamide-β-D-riboside-2,3,5-triacetic acid L-tartrate : 3.00 g of nicotinamide-β-D-riboside-2,3,5-triacetic acid L-tartrate was suspended in 15 ml of methanol under stirring. After adding 11.7 g of the above methanolic sulfuric acid, a light yellow solution was generated. After stirring at room temperature for 5 days, thin layer chromatography was performed to detect that only the product and nicotinamide as an impurity were present.

[0475] After neutralization with triethylamine, it is converted into nicotinamide-β-D-riboside L-tartrate: 1.1 ml of triethylamine was added to the above solution to adjust the pH to about 3.5. 0.85 g of L-tartaric acid was added. After the addition of 0.8 ml of triethylamine, the product began to crystallize. The suspension was stirred for another hour and then stored in a refrigerator for 12 hours. The crystals formed were filtered off, washed with isopropanol and dried in vacuo at 30° C. 1.01 g (44.2%) of a white crystalline powder with a melting point of 126-127° C. was obtained.

[0476] 1 H-NMR (400MHz, D2O): 3.82 (dd, 1H, H5'), 3.96 (dd, 1H, H5'), 4.27 (t, 1H, H3'), 4.37-4.45 (m, 2H, H4', H2'), 4.42 (s, 2H, 2x CHOH, H-tartaric acid), 6.17 (d, 1H, H1'), 8.20 (t, 1H, H5), 8.90 (d, 1H, H4), 9.19 (d, 1H, H6), 9.52 (s, 1H, H2). Impurities: 3 mol% nicotinamide: 7.85 (m, 1H), 8.56 (m, 1H), 8.77 (d, 1H), 9.00 (s, 1H); 3.4 mol% TEA salt: 1.18 (t, 9H), 3.11 (q, 6H). Solvent: 11.3 mol% Methanol: 3.25 (s, 3H).

[0477] 13 C-NMR (100 MHz, D2O): 60.2 (C5'), 69.7 (C3'), 72.8 (2x CHOH, H-tartaric acid), 77.4 (C2'), 87.6 (C4'), 99.9 (C1'), 128.4 (C5), 133.9 (C3), 140.4 (C2), 142.6 (C6), 145.6 (C4), 165.8 (CONH2), 176.3 (2x COO, H-tartaric acid). Impurities: 8.2, 46.6 (TEA salt). Solvent: 48.9 (methanol).

[0478] Example 15b: Deacylation with HBr in glacial acetic acid and neutralization with triethylamine

[0479] Deacylation of Nicotinamide-β-D-riboside-2,3,5-triacetic acid L-tartrate : 3.0 g of nicotinamide-β-D-riboside-2,3,5-triacetic acid L-tartrate was suspended in 15 ml of methanol under stirring. The suspension was cooled to 5°C and 3.0 ml of 33% HBr glacial acetic acid solution was added. A pale yellow solution was formed, which was stirred at room temperature for three days. Thin layer chromatography showed that the deacylation was complete.

[0480] After neutralization with triethylamine, it is converted into nicotinamide-β-D-riboside L-tartrate: 1 ml of triethylamine was added to the above solution in portions. 1.5 ml of water was added to form a yellow solution. Subsequently, 0.85 g of L-tartaric acid was added. After the addition of 0.8 ml of triethylamine, the product began to crystallize. The product suspension was stirred at room temperature for another hour. The formed crystals were filtered off, washed with 7 ml of isopropanol and 5 ml of acetone, and dried in vacuo at 30° C. 0.82 g (36%) of a white crystalline powder with a melting point of 129 to 130° C. was obtained.

[0481] 1 H-NMR (400 MHz, D2O): Similar to Example 15a. Impurities: 1 mol% nicotinamide; 0.1 mol% TEA salt. Solvent: 2.7 mol% methanol.

[0482] 13 C-NMR (100 MHz, D2O): similar to Example 15a.

[0483] Example 16: Deacylation of Nicotinamide-2,3,5-Tri-O-Acetyl-β-D-Ribofuranoside Bromide (from Example 1) Illustrative of Pathway 3

[0484] Example 16a: Deacylation with sulfuric acid and neutralization with triethylamine

[0485] Preparation of dilute sulfuric acid in methanol : Cool 20 ml of methanol to 0°C. Add 2.00 g of 96% sulfuric acid while stirring to obtain 21 ml of 0.93 M methanolic sulfuric acid.

[0486] Deacylation of Nicotinamide-2,3,5-Tri-O-Acetyl-β-D-Ribofuranosyl Bromide : Under stirring, 5.00 g of nicotinamide-2,3,5-tri-O-acetyl-β-D-ribofuranoside bromide was suspended in 24.4 ml of methanol, in which part of the educt was dissolved. 5.6 ml of the above methanolic sulfuric acid was added. The resulting colorless solution was stirred at room temperature. The solution was stirred for three days to produce a suspension.

[0487] After neutralization with triethylamine, it is converted into nicotinamide-β-D-riboside L-tartrate: To the above suspension was added 1.36 ml of triethylamine. After addition of 3.4 ml of water, a colorless solution was obtained. After addition of 1.63 g of L-tartaric acid, the product began to precipitate. After addition of another 1.35 ml of triethylamine, further product precipitated. The suspension was filtered, the solid obtained was washed with methanol and dried in vacuo at 30°C. 2.4 g (55%) of a white crystalline powder was obtained. Mp. 129.5°C. IC: Residual bromide 0.05%.

[0488] 1 H-NMR (400MHz, D2O): 3.82 (dd, 1H, H5'), 3.96 (dd, 1H, H5'), 4.27 (t, 1H, H3'), 4.37-4.45 (m, 2H, H4', H2'), 4.42 (s, 2H, 2x CHOH, H-tartaric acid), 6.17 (d, 1H, H1'), 8.20 (t, 1H, H5), 8.90 (d, 1H, H4), 9.19 (d, 1H, H6), 9.52 (s, 1H, H2). Impurities: 2mol% nicotinamide: 7.83 (m, 1H), 8.54 (m, 1H), 8.76 (d, 1H), 9.00 (s, 1H); 0.7mol% TEA salt: 1.19 (t, 9H), 3.11 (q, 6H). Solvent: 7 mol% methanol: 3.25 (s, 3H).

[0489] 13 C-NMR (100 MHz, D2O): 60.2 (C5'), 69.7 (C3'), 72.8 (2x CHOH, H-tartaric acid), 77.4 (C2'), 87.6 (C4'), 99.9 (C1'), 128.4 (C5), 133.9 (C3), 140.4 (C2), 142.6 (C6), 145.6 (C4), 165.8 (CONH2), 176.3 (2x COO, H-tartaric acid). Solvent: 48.9 (methanol).

[0490] Example 16b: Deacylation with HBr in glacial acetic acid and neutralization with triethylamine

[0491] Deacylation of Nicotinamide-2,3,5-tri-O-acetyl-β-D-ribofuranoside Bromide: 5.00 g of nicotinamide-2,3,5-tri-O-acetyl-β-D-ribofuranoside bromide was dissolved in 30 ml of methanol under stirring at room temperature. After adding 3.75 ml of 33% HBr glacial acetic acid solution, the resulting yellow solution was stirred at room temperature for three days. Controlled by thin layer chromatography, a white suspension of nicotinamide-β-D-ribofuranoside bromide was obtained.

[0492] After neutralization with triethylamine, nicotinamide-β-D-ribofuranoside was converted to nicotinamide-β-D-ribofuranoside L- Bitartrate:2.50 ml of triethylamine were added to the above suspension in portions. Subsequently, 2.5 ml of water were added. 1.63 g of L-tartaric acid were added to the light yellow solution formed. After a further addition of 1.52 ml of triethylamine, the product began to precipitate at a pH of 3.5 to 4. The crystalline product was filtered off, washed with 10 ml of isopropanol and 10 ml of acetone and dried in vacuo at 30° C. 2.93 g (66.9%) of a white crystalline powder were obtained. Mp. 127.5 to 128.5° C. IC: Residual bromide 0.33%.

[0493] 1H-NMR (400 MHz, D2O): Similar to Example 15a. Impurities: 1 mol% nicotinamide; 2.3 mol% TEA salt. Solvent: 7 mol% methanol.

[0494] 13C-NMR (100 MHz, D2O): similar to Example 15a.

[0495] Example 16c: Deacylation using triethylamine

[0496] 5.00 g of nicotinamide-2,3,5-tri-O-acetyl-β-D-ribofuranoside bromide were dissolved in 30 ml of methanol with stirring at room temperature. 1.52 ml of triethylamine (1 eq) were added. The yellow solution was stirred for 24 hours. Thin layer chromatography control showed almost complete conversion, but nicotinamide was also formed. 1.63 g of L-tartaric acid were added to the suspension formed. The product began to precipitate. The product suspension was stirred at 0° C. for 1 hour, the product formed was separated by filtration, washed with 12 ml of isopropanol and 12 ml of acetone and dried in vacuo at 30° C. 1.86 g (42.4%) of a white powder were obtained. Mp. 127° C.; IC: residual bromide 0.26%.

[0497] 1H-NMR (400 MHz, D2O): Similar to Example 15a. Impurities: 6 mol% nicotinamide; 1.7 mol% TEA salt. Solvent: 18 mol% methanol, 0.5 mol% isopropanol.

[0498] 13C-NMR (100 MHz, D2O): similar to Example 15a.

[0499] Example 16d: Deacylation using triethylamine at 0-5°C

[0500] Example 16c was repeated except that nicotinamide-2,3,5-tri-O-acetyl-β-D-ribofuranoside bromide was subjected to triethylamine treatment at 0° C. The yield increased to 85.8%.

[0501] Example 17: Illustrative of the preparation of nicotinamide-β-D-riboside-2,3,5-triacetic acid L-tartrate of route 4, obtained by separating the L-tartrate from a mixture of β- and α-anomers produced by glycosylation of nicotinamide with 1-bromo-2,3,5-triacetyl-D-ribofuranoside

[0502] 100 ml of the crude mixture of anomers (obtained analogously to Example 1) containing theoretically 54 mmol of nicotinamide-D-ribofuranoside-2,3,5-triacetate, in which the acids (HBr and acetic acid) contained were partially neutralized, were added. 5.16 g of L-tartaric acid were added to the orange-yellow solution under stirring. Once the tartaric acid was completely dissolved, 4.8 ml of triethylamine were added.

[0503] The solution was concentrated by distilling off 42 ml of solution, and needle-like triethylamine hydrobromide began to precipitate. 30 ml of isopropanol were added and the suspension was cooled to 0° C. with stirring. The suspension was filtered and the residue (triethylamine hydrobromide) was washed with 14 ml of isopropanol.

[0504] The filtrate was inoculated with some product crystals. Subsequently, 30 ml of tert-butyl methyl ether was slowly added and the product began to precipitate. The product was stored in a refrigerator for 12 hours. After filtration, it was washed twice with 25 ml of isopropanol, and the solid was dried in vacuo at 35°C. 13.86 g (48.5%) of nicotinamide-β-D-riboside-2,3,5-triacetic acid L-tartrate was obtained in the form of white crystals. Mp.123-124°C; IC: residual bromide 2.64%.

[0505] 1 H-NMR (400MHz, D2O): 2.08, 2.12, 2.15 (3x s, 3x 3H, COCH3), 4.43 (s, 2H, 2xCHOH, H-tartaric acid), 4.52 (m, 2H, H5'), 4.88 (m, 1H, H4'), 5.44 (t, 1H, H3'), 5.56 (dd, 1H, H2'), 6.58 (d, 1H, H1'), 8.27 (t, 1H, H5), 8.99 (d, 1H, H4), 9.20 (d, 1H, H6), 9.43 (s, 1H, H2). Impurities: <1mol% nicotinamide; 20mol% TEA salt: 1.21 (t, 9H), 3.13 (q, 6H). Solvent: 2.2 mol% isopropanol: 1.09 (d, 6H), 3.93 (m, 1H).

[0506] 13C-NMR (100 MHz, D2O): 19.8, 19.9, 20.2 (3x COCH3), 62.6 (C5'), 69.4 (C3'), 72.8 (2x CHOH, H-tartaric acid), 76.3 (C2'), 82.6 (C4'), 97.3 (C1'), 128.6 (C5), 134.2 (C3), 140.4 (C2), 143.1 (C6), 146.2 (C4), 165.5 (CONH2), 172.3, 172.4, 173.3 (3xCO), 176.3 (2x COO, H-tartaric acid). Impurities: TEA salt: 8.2, 46.7.

[0507] Example 18: Deacylation of the Anomeric Mixture of Nicotinamide-α / β-D-riboside-2,3,5-triacetic Acid Bromide Illustrated in Pathway 5

[0508] 100 ml of the crude solution containing the anomer (see Example 1), which theoretically contains about 54 mmol of nicotinamide-D-ribofuranoside-2,3,5-triacetic acid bromide, was completely concentrated by using a rotary evaporator in a temperature range of 35-40°C. The resulting yellow viscous oil was diluted with 44 ml of methanol. Subsequently, 10 ml of a 33% HBr glacial acetic acid solution was added. The pale yellow transparent solution was stirred at room temperature. After one day, nicotinamide-β-D-riboside bromide precipitated. After 5 days, complete deacylation was achieved by thin layer chromatography control.

[0509] Separation of Nicotinamide-β-D-riboside L-tartrate : To the above suspension was added 7.5 ml of triethylamine to neutralize HBr and acetic acid. After adding 4 ml of water, a clear solution was obtained. To the pale yellow solution was added 8.6 g of tartaric acid and filtered to remove insoluble precipitates. Subsequently, 5.4 ml of triethylamine was added, wherein the desired product began to precipitate. After filtering and washing with ethanol and methanol, the resulting solid was dried in vacuo at 30°C. 7.27 g (33.3%) of a white crystalline powder was obtained. Mp. 128.5-129.5°C; IC: residual bromide 0.16%.

[0510] 1 H-NMR (400 MHz, D2O): Similar to Example 15a. Impurities: 3 mol% nicotinamide; 1.2 mol% TEA salt. Solvent: 7 mol% methanol.

[0511] 13 C-NMR (100 MHz, D2O): similar to Example 15a.

[0512] Example 19: Deacylation of Nicotinamide-β-D-riboside-2,3,5-triacetic acid trifluoromethanesulfonate illustrating Pathway 5:

[0513] Example 19a: Deacylation with sulfuric acid and neutralization with triethylamine

[0514] Preparation of dilute sulfuric acid in methanol : Cool 27 g of methanol to 0°C. Add 3.00 g of 96% sulfuric acid under stirring to obtain 30 g of 10% methanolic sulfuric acid.

[0515] Deacylation of Nicotinamide-2,3,5-Tri-O-Acetyl-β-D-Ribofuranoside Trifluoromethanesulfonate : 3.00 g of nicotinamide-2,3,5-tri-O-acetyl-β-D-ribofuranoside trifluoromethanesulfonate was dissolved in 15 ml of methanol under stirring. 5.86 g of the above methanolic sulfuric acid was added. The resulting colorless solution was stirred at room temperature. The solution was stirred for three days. TLC control showed complete deacylation and some nicotinamide impurity.

[0516] After neutralization with triethylamine, it is converted into nicotinamide-β-D-riboside L-tartrate : 1.1 ml of triethylamine were added to the above solution. 3.3 ml of a 1.7 molar methanol solution of L-triethylammonium hydrogen tartrate were added, wherein the product immediately began to precipitate. Subsequently, 0.40 g of L-tartaric acid was added. The product suspension was stored in a refrigerator for 12 hours. After filtration, the solid obtained was washed with methanol and ethanol and dried in vacuo at 30° C. 1.23 g (53.8%) of a white crystalline powder was obtained. Mp. 127 to 128° C.

[0517] 1 H-NMR (400MHz, D2O): 3.82 (dd, 1H, H5'), 3.96 (dd, 1H, H5'), 4.27 (t, 1H, H3'), 4.37-4.45 (m, 2H, H4', H2'), 4.41 (s, 2H, 2x CHOH, H-tartaric acid), 6.17 (d, 1H, H1'), 8.20 (t, 1H, H5), 8.90 (d, 1H, H4), 9.19 (d, 1H, H6), 9.51 (s, 1H, H2). Impurities: 2mol% nicotinamide: 7.83 (m, 1H), 8.54 (m, 1H), 8.76 (d, 1H), 9.00 (s, 1H); 2.9mol% TEA salt: 1.19 (t, 9H), 3.11 (q, 6H). Solvent: 16 mol% methanol: 3.25 (s, 3H), 2 mol% ethanol.

[0518] 13C-NMR (100 MHz, D2O): 60.2 (C5'), 69.7 (C3'), 72.8 (2x CHOH, H-tartaric acid), 77.4 (C2'), 87.6 (C4'), 99.9 (C1'), 128.4 (C5), 133.9 (C3), 140.4 (C2), 142.6 (C6), 145.6 (C4), 165.8 (CONH2), 176.3 (2x COO, H-tartaric acid). Impurities: 8.2, 46.6 (TEA salt). Solvent: 48.9 (methanol).

[0519] Example 19b: Deacylation with HBr in glacial acetic acid and neutralization with triethylamine

[0520] 8.00 g of nicotinamide-2,3,5-tri-O-acetyl-β-D-furanosyl trifluoromethanesulfonate was dissolved in 32 ml of methanol under stirring. The solution was cooled to 0-5°C. After adding 5.2 ml of 33% HBr glacial acetic acid solution, the solution was kept stirring at room temperature. According to the control of thin layer chromatography, the product was deacylated after two days.

[0521] The solution was divided in half.

[0522] Separation of the intermediate bromide formed : Half of the solution (20.5 ml) was seeded with nicotinamide-β-D-ribofuranoside bromide and stirred at room temperature. A suspension was formed after about 30 minutes. The suspension was filtered and the residue was washed with methanol and ethanol and then dried in vacuo at 30°C. 0.62 g (24.5%) of a white crystalline powder was obtained.

[0523] 1 H-NMR(400MHz,D2O): 3.83(dd,1H,H5'),3.98(dd,1H,H5'),4.29(t,1H,H3'),4.39-4.48(m,2H, H4',H2'),6.18(d,1H,H1'),8.22(t,1H,H5),8.92(d,1H,H4),9.20(d,1H,H6),9.52(s,1H,H2).

[0524] 13 C-NMR(100MHz,D2O): 60.2(C5'),69.7(C3'),77.4(C2'),87.7(C4'),99.9(C1 '),128.5(C5),134.0(C3),140.4(C2),142.7(C6),145.7(C4),165.8(CONH2).

[0525] After neutralization with triethylamine, it is converted into nicotinamide-β-D-riboside L-tartrate:1.8 ml of triethylamine was added to the other half of the solution, in which HBr and acetic acid were partially neutralized. 4.4 ml of a 1.7 molar methanolic solution of triethylammonium L-tartrate was added to the pale yellow solution, in which the product began to precipitate. After filtering and washing with methanol and ethanol and drying in vacuo at 30° C., 1.62 g (53.2%) of a white crystalline powder was obtained. Mp. 127-128° C.

[0526] 1 H-NMR (400 MHz, D2O): Similar to Example 19a. Impurities: 1 mol% nicotinamide; 3.7 mol% TEA salt. Solvent: 12.5 mol% methanol.

[0527] 13 C-NMR (100 MHz, D2O): similar to Example 19a.

[0528] Example 19c: Deacylation using triethylamine

[0529] Deacylation of Nicotinamide-D-riboside-2,3,5-triacetic acid trifluoromethanesulfonate : 3.00 g of triflate are dissolved in 18 ml of methanol under stirring. 0.8 ml of triethylamine (1 eq) are added to the solution cooled to 0° C. After stirring at 0-5° C. for 4 days, thin layer control shows complete conversion.

[0530] Converted to Nicotinamide-β-D-riboside L-tartrate : The brown-orange solution obtained in the above step was heated to room temperature. Subsequently, 0.86 g of L-tartaric acid was added. The product began to precipitate. The product suspension was cooled to 0°C and stirred. After storage in a refrigerator for 12 hours, the suspension was filtered and the solid obtained was washed with 5 ml of isopropanol and dried in vacuo at 30°C. 1.44 g (63.0%) of brown-yellow crystalline powder was obtained. Mp. 127°C.

[0531] 1 H-NMR (400 MHz, D2O): Similar to Example 19a. Impurities: 2 mol% nicotinamide; 1.9 mol% TEA salt. Solvent: 13.3 mol% methanol, 4 mol% isopropanol.

[0532] 13 C-NMR (100 MHz, D2O): similar to Example 19a.

[0533] Since one equivalent of triethylamine is required for deacylation in the above sequence, it can be concluded that triethylamine is unexpectedly catalytically active.

[0534] Example 19d: Deacylation using HBr in glacial acetic acid and neutralization using tributylamine

[0535] Deacylation of Nicotinamide-2,3,5-Tri-O-acetyl-D-ribofuranoside Trifluoromethanesulfonate: 2.00 g of triflate was dissolved in 8 ml of methanol under stirring. The solution was cooled to 0-5°C. After adding 1.3 ml of 33% HBr glacial acetic acid solution, the yellow-green solution was stirred at room temperature. After two days, no educt could be identified in the solution by thin layer chromatography.

[0536] After neutralization with tributylamine, it is converted into nicotinamide-β-D-furanosyl glycoside L-malate 1.3 ml of tributylamine was added to the above solution. After adding 0.6 ml of water, any precipitate was completely dissolved. 0.51 g of L-malic acid was added to the brown-yellow solution. After adding 0.9 ml of tributylamine, the product began to crystallize. The formed product was filtered off, washed with methanol and dried in vacuo at 30°C. 0.48 g (33%) of nicotinamide-β-D-furanosyl L-malate was obtained. Mp. 115.5-116.5°C.

[0537] 1 H-NMR (400 MHz, D2O): 2.55 (dd, 1H, CH2, H-malic acid), 2.73 (dd, 1H, CH2, H-malic acid), 3.83 (dd, 1H, H5'), 3.98 (dd, 1H, H5'), 4.28 (t, 1H, H3'), 4.29 (dd, 1H, CHOH, H-malic acid), 4.39-4.46 (m, 2H, H 4', H2'), 6.18 (d, 1H, H1'), 8.21 (t, 1H, H5), 8.91 (d, 1H, H4), 9.20 (d, 1H, H6), 9.53 (s, 1H, H2). Impurities: <1 mol% nicotinamide; 0.35 mol% TBA salt: 0.85 (t, 9H), 1.29 (m, 6H), 1.59 (m, 6H), 3.05 (q, 6H). Solvent: 2.3 mol% methanol: 3.27 (s, 3H).

[0538] 13 C-NMR (100 MHz, D2O): 40.0 (CH2, H-malic acid), 60.2 (C5'), 68.5 (CHOH, H-malic acid), 69.8 (C3'), 77.4 (C2'), 87.7 (C4'), 99.9 (C1'), 128.4 (C5), 133.9 (C3), 140.4 (C2), 142.6 (C6), 145.6 (C4), 165.8 (CONH2), 176.3 (COO, H-malic acid), 179.0 (COO, H-malic acid).

[0539] Example 20: Preparation of Nicotinamide-2,3,5-Tri-O-Acetyl-β-D-Ribofuranosyl Iodide

[0540] At room temperature, 6.00 g (0.049 mole) of nicotinamide and 14.9 g (0.047 mole) of β-D-ribofuranose 1,2,3,5-tetraacetate were suspended in 190 ml of a mixture of 4% iodine and 1% iodine. The suspension was heated to 35°C while most of the solid dissolved. 6.9 ml (0.048 mol) of trimethylsilyl iodide was added over 20 minutes and the yellow suspension was stirred at 35°C for another 2 hours. Subsequently, the internal temperature was maintained at 40°C and 45°C for one hour respectively. The solvent was removed in vacuo at 35°C. The foam formed was dissolved in 100 ml of dichloromethane and 1.2 g of activated carbon was added. The suspension was filtered. The filtrate was concentrated. 22 g (93%) of dark yellow foam was obtained.

[0541] 1 H-NMR (400 MHz, D2O): 2.05, 2.07, 2.12 (3x s, 3x 3H, COCH3), 4.46 (m, 2H, H5'), 4.84 (m, 1H, H4'), 5.41 (t, 1H, H3'), 5.53 (dd, 1H, H2'), 6.58 (d, 1H, H1'), 8.28 (t, 1H, H5), 8.94 (d, 1H, H4), 9.18 (d, 1H, H6), 9.38 (s, 1H, H2). Impurities: 15 mol% α-anomer, 3 mol% nicotinamide.

[0542] 13 C-NMR(100MHz,D2O):20.0,20.1,20.4(3x COCH3),62.6(C5'),69.3(C3'),76.1(C2'),82.5(C4'),97.2(C1'),128.8(C5),134 .1(C3),140.4(C2),143.1(C6),146.2(C4),165.1(CONH2),172.0,172.1,173.0(3x CO).

[0543] Example 21: Deacylation of Nicotinamide-β-D-riboside-2,3,5-triacetic Acid Iodide Illustrated in Pathway 5:

[0544] Deacylation with sulfuric acid and neutralization with triethylamine

[0545] Preparation of dilute sulfuric acid in methanol : Cool 10 ml of methanol to 0°C. Add 1.20 ml of 96% sulfuric acid under stirring. Methanolic sulfuric acid is used for the following deacylation.

[0546] Deacylation of Nicotinamide-2,3,5-tri-O-acetyl-β-D-ribofuranoside iodide: 11.0 g Nicotinamide-2,3,5-tri-O-acetyl-β-D-ribofuranoside iodide was dissolved in 33 ml of methanol under stirring. The methanolic sulfuric acid prepared above was added. The resulting orange-brown solution was stirred at room temperature for 1 day. TLC control showed complete deacylation and some impurities. 3.5 ml of triethylamine was added.

[0547] The solution was divided in half.

[0548] After neutralization with triethylamine, it is converted into nicotinamide-β-D-riboside L-tartrate : To half of the above solution, 1.65 g of L-tartaric acid was added, followed by 1.6 ml of triethylamine. The product began to precipitate almost immediately. The product suspension was stirred at ambient temperature for 1 hour, in an ice bath for 2 hours, and stored in a refrigerator for 12 hours. After filtration, the resulting solid was washed with methanol and dried in vacuo at 30°C. 2.10 g (48%) of nicotinamide-β-D-ribofuranoside L-tartrate was obtained as an almost white crystalline powder. Mp. 125.5-126°C. 1 H-NMR (400 MHz, D2O): Similar to Example 19a. Impurities: 1 mol% nicotinamide; 3.8 mol% TEA salt. Solvent: 18.2 mol% methanol.

[0549] 13 C-NMR (100 MHz, D2O): similar to Example 19a.

[0550] After neutralization with triethylamine, it is converted into nicotinamide-β-D-riboside L-malate : To the other half of the above solution, 1.45 g of L-malic acid was added, followed by 1.1 ml of triethylamine. The solution was seeded. After a few minutes, the product began to precipitate. The product suspension was stirred at ambient temperature for 1 hour and in an ice bath for 2 hours, then stored in a refrigerator for 12 hours. After filtration, the resulting solid was washed with methanol and ethanol and dried in vacuo at 30°C. 1.37 g (32.7%) of nicotinamide-β-D-furanosyl glycoside L-malic acid hydrogen salt was obtained as an almost white crystalline solid. Mp. 114-115°C.

[0551] 1 H-NMR (400 MHz, D2O): Similar to Example 19d. Impurities: 0.5 mol% nicotinamide; 0.5 mol% TEA salt. Solvent: 2.4 mol% methanol, 0.4 mol% ethanol.

[0552] 13 C-NMR (100 MHz, D2O): similar to Example 19d.

Claims

1. A crystalline form of nicotinamide-β-D-ribofuranoside L-malate, wherein the crystalline form is characterized by a powder X-ray diffraction pattern having one or more peaks provided in Table 2, ±0.2 degrees 2θ.

2. The crystalline form of claim 1, wherein the crystalline form is characterized by a powder X-ray diffraction pattern having the following peaks: 19.8±0.2 degrees 2θ, 21.5±0.2 degrees 2θ, and 25.8±0.2 degrees 2θ.

3. The crystalline form of claim 1, wherein the crystalline form is characterized by a powder X-ray diffraction pattern having the following peaks: 17.7±0.2 degrees 2θ, 27.3±0.2 degrees 2θ, and 28.6±0.2 degrees 2θ.

4. The crystalline form of claim 1, wherein the crystalline form is characterized by a powder X-ray diffraction pattern having the following peaks: 17.7±0.2 degrees 2θ, 19.8±0.2 degrees 2θ, 21.5±0.2 degrees 2θ, 25.8±0.2 degrees 2θ, 27.3±0.2 degrees 2θ, and 28.6±0.2 degrees 2θ.

5. The crystalline form according to any one of claims 1 to 4, wherein the crystalline form is crystalline nicotinamide-β-D-ribofuranoside L-malate, characterized in that Powder X-ray diffraction pattern as defined in Figure 2.

6. A crystalline form of nicotinamide-β-D-ribofuranoside D-malate, wherein the crystalline form is characterized by a powder X-ray diffraction pattern having one or more peaks provided in Table 1, ± 0.2 degrees 2θ.

7. The crystalline form of claim 6, wherein the crystalline form is characterized by a powder X-ray diffraction pattern having the following peaks: 22.5±0.2 degrees 2θ, 24.1±0.2 degrees 2θ, and 26.0±0.2 degrees 2θ.

8. The crystalline form of claim 6, wherein the crystalline form is characterized by a powder X-ray diffraction pattern having the following peaks: 16.6 ± 0.2 degrees 2θ, 22.5 ± 0.2 degrees 2θ, 24.1 ± 0.2 degrees 2θ.

9. The crystalline form according to any one of claims 6 to 8, wherein the crystalline form is crystalline nicotinamide-β-D-ribofuranoside D-malate, characterized in that Powder X-ray diffraction pattern as defined in Figure 1.

10. A crystalline form of nicotinamide-β-D-ribofuranoside DL-malate, wherein the crystalline form is characterized by a powder X-ray diffraction pattern having one or more peaks provided in Table 3, ± 0.2 degrees 2θ.

11. The crystalline form of claim 10, wherein the crystalline form is characterized by a powder X-ray diffraction pattern having the following peaks: 16.7±0.2 degrees 2θ, 24.2±0.2 degrees 2θ, and 26.0±0.2 degrees 2θ.

12. The crystalline form of claim 10, wherein the crystalline form is characterized by a powder X-ray diffraction pattern having the following peaks: 12.7 ± 0.2 degrees 2θ, 22.5 ± 0.2 degrees 2θ, 25.0 ± 0.2 degrees 2θ.

13. The crystalline form according to any one of claims 10 to 12, wherein the crystalline form is crystalline nicotinamide-β-D-ribofuranoside DL-malate, characterized in that Powder X-ray diffraction pattern as defined in Figure 3.

14. A nutritional supplement comprising the crystalline form according to any one of claims 1 to 13.

15. A pharmaceutical composition comprising the crystalline form according to any one of claims 1 to 13.

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